diff --git a/internal/api/handlers/management/auth_files.go b/internal/api/handlers/management/auth_files.go
index e626af47..5909dffc 100644
--- a/internal/api/handlers/management/auth_files.go
+++ b/internal/api/handlers/management/auth_files.go
@@ -1722,6 +1722,17 @@ func (h *Handler) RequestIFlowCookieToken(c *gin.Context) {
 		return
 	}
 
+	// Check for duplicate BXAuth before authentication
+	bxAuth := iflowauth.ExtractBXAuth(cookieValue)
+	if existingFile, err := iflowauth.CheckDuplicateBXAuth(h.cfg.AuthDir, bxAuth); err != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{"status": "error", "error": "failed to check duplicate"})
+		return
+	} else if existingFile != "" {
+		existingFileName := filepath.Base(existingFile)
+		c.JSON(http.StatusConflict, gin.H{"status": "error", "error": "duplicate BXAuth found", "existing_file": existingFileName})
+		return
+	}
+
 	authSvc := iflowauth.NewIFlowAuth(h.cfg)
 	tokenData, errAuth := authSvc.AuthenticateWithCookie(ctx, cookieValue)
 	if errAuth != nil {
@@ -1744,11 +1755,12 @@ func (h *Handler) RequestIFlowCookieToken(c *gin.Context) {
 	}
 
 	tokenStorage.Email = email
+	timestamp := time.Now().Unix()
 
 	record := &coreauth.Auth{
-		ID:       fmt.Sprintf("iflow-%s.json", fileName),
+		ID:       fmt.Sprintf("iflow-%s-%d.json", fileName, timestamp),
 		Provider: "iflow",
-		FileName: fmt.Sprintf("iflow-%s.json", fileName),
+		FileName: fmt.Sprintf("iflow-%s-%d.json", fileName, timestamp),
 		Storage:  tokenStorage,
 		Metadata: map[string]any{
 			"email":        email,
diff --git a/internal/auth/iflow/cookie_helpers.go b/internal/auth/iflow/cookie_helpers.go
index 6848f4b0..7e0f4264 100644
--- a/internal/auth/iflow/cookie_helpers.go
+++ b/internal/auth/iflow/cookie_helpers.go
@@ -1,7 +1,10 @@
 package iflow
 
 import (
+	"encoding/json"
 	"fmt"
+	"os"
+	"path/filepath"
 	"strings"
 )
 
@@ -36,3 +39,61 @@ func SanitizeIFlowFileName(raw string) string {
 	}
 	return strings.TrimSpace(result.String())
 }
+
+// ExtractBXAuth extracts the BXAuth value from a cookie string.
+func ExtractBXAuth(cookie string) string {
+	parts := strings.Split(cookie, ";")
+	for _, part := range parts {
+		part = strings.TrimSpace(part)
+		if strings.HasPrefix(part, "BXAuth=") {
+			return strings.TrimPrefix(part, "BXAuth=")
+		}
+	}
+	return ""
+}
+
+// CheckDuplicateBXAuth checks if the given BXAuth value already exists in any iflow auth file.
+// Returns the path of the existing file if found, empty string otherwise.
+func CheckDuplicateBXAuth(authDir, bxAuth string) (string, error) {
+	if bxAuth == "" {
+		return "", nil
+	}
+
+	entries, err := os.ReadDir(authDir)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return "", nil
+		}
+		return "", fmt.Errorf("read auth dir failed: %w", err)
+	}
+
+	for _, entry := range entries {
+		if entry.IsDir() {
+			continue
+		}
+		name := entry.Name()
+		if !strings.HasPrefix(name, "iflow-") || !strings.HasSuffix(name, ".json") {
+			continue
+		}
+
+		filePath := filepath.Join(authDir, name)
+		data, err := os.ReadFile(filePath)
+		if err != nil {
+			continue
+		}
+
+		var tokenData struct {
+			Cookie string `json:"cookie"`
+		}
+		if err := json.Unmarshal(data, &tokenData); err != nil {
+			continue
+		}
+
+		existingBXAuth := ExtractBXAuth(tokenData.Cookie)
+		if existingBXAuth != "" && existingBXAuth == bxAuth {
+			return filePath, nil
+		}
+	}
+
+	return "", nil
+}
diff --git a/internal/auth/iflow/iflow_auth.go b/internal/auth/iflow/iflow_auth.go
index 2978e94c..fa9f38c3 100644
--- a/internal/auth/iflow/iflow_auth.go
+++ b/internal/auth/iflow/iflow_auth.go
@@ -494,11 +494,18 @@ func (ia *IFlowAuth) CreateCookieTokenStorage(data *IFlowTokenData) *IFlowTokenS
 		return nil
 	}
 
+	// Only save the BXAuth field from the cookie
+	bxAuth := ExtractBXAuth(data.Cookie)
+	cookieToSave := ""
+	if bxAuth != "" {
+		cookieToSave = "BXAuth=" + bxAuth + ";"
+	}
+
 	return &IFlowTokenStorage{
 		APIKey:      data.APIKey,
 		Email:       data.Email,
 		Expire:      data.Expire,
-		Cookie:      data.Cookie,
+		Cookie:      cookieToSave,
 		LastRefresh: time.Now().Format(time.RFC3339),
 		Type:        "iflow",
 	}
diff --git a/internal/cmd/iflow_cookie.go b/internal/cmd/iflow_cookie.go
index b1cb1f9c..358b8062 100644
--- a/internal/cmd/iflow_cookie.go
+++ b/internal/cmd/iflow_cookie.go
@@ -5,7 +5,9 @@ import (
 	"context"
 	"fmt"
 	"os"
+	"path/filepath"
 	"strings"
+	"time"
 
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/auth/iflow"
 	"github.com/router-for-me/CLIProxyAPI/v6/internal/config"
@@ -37,6 +39,16 @@ func DoIFlowCookieAuth(cfg *config.Config, options *LoginOptions) {
 		return
 	}
 
+	// Check for duplicate BXAuth before authentication
+	bxAuth := iflow.ExtractBXAuth(cookie)
+	if existingFile, err := iflow.CheckDuplicateBXAuth(cfg.AuthDir, bxAuth); err != nil {
+		fmt.Printf("Failed to check duplicate: %v\n", err)
+		return
+	} else if existingFile != "" {
+		fmt.Printf("Duplicate BXAuth found, authentication already exists: %s\n", filepath.Base(existingFile))
+		return
+	}
+
 	// Authenticate with cookie
 	auth := iflow.NewIFlowAuth(cfg)
 	ctx := context.Background()
@@ -82,5 +94,5 @@ func promptForCookie(promptFn func(string) (string, error)) (string, error) {
 // getAuthFilePath returns the auth file path for the given provider and email
 func getAuthFilePath(cfg *config.Config, provider, email string) string {
 	fileName := iflow.SanitizeIFlowFileName(email)
-	return fmt.Sprintf("%s/%s-%s.json", cfg.AuthDir, provider, fileName)
+	return fmt.Sprintf("%s/%s-%s-%d.json", cfg.AuthDir, provider, fileName, time.Now().Unix())
 }
diff --git a/internal/runtime/executor/openai_compat_executor.go b/internal/runtime/executor/openai_compat_executor.go
index ac932c0b..d4b0afcb 100644
--- a/internal/runtime/executor/openai_compat_executor.go
+++ b/internal/runtime/executor/openai_compat_executor.go
@@ -54,13 +54,14 @@ func (e *OpenAICompatExecutor) Execute(ctx context.Context, auth *cliproxyauth.A
 	from := opts.SourceFormat
 	to := sdktranslator.FromString("openai")
 	translated := sdktranslator.TranslateRequest(from, to, req.Model, bytes.Clone(req.Payload), opts.Stream)
-	if modelOverride := e.resolveUpstreamModel(req.Model, auth); modelOverride != "" {
+	modelOverride := e.resolveUpstreamModel(req.Model, auth)
+	if modelOverride != "" {
 		translated = e.overrideModel(translated, modelOverride)
 	}
 	translated = applyPayloadConfigWithRoot(e.cfg, req.Model, to.String(), "", translated)
 	translated = applyReasoningEffortMetadata(translated, req.Metadata, req.Model, "reasoning_effort")
 	upstreamModel := util.ResolveOriginalModel(req.Model, req.Metadata)
-	if upstreamModel != "" {
+	if upstreamModel != "" && modelOverride == "" {
 		translated, _ = sjson.SetBytes(translated, "model", upstreamModel)
 	}
 	translated = normalizeThinkingConfig(translated, upstreamModel)
@@ -148,13 +149,14 @@ func (e *OpenAICompatExecutor) ExecuteStream(ctx context.Context, auth *cliproxy
 	from := opts.SourceFormat
 	to := sdktranslator.FromString("openai")
 	translated := sdktranslator.TranslateRequest(from, to, req.Model, bytes.Clone(req.Payload), true)
-	if modelOverride := e.resolveUpstreamModel(req.Model, auth); modelOverride != "" {
+	modelOverride := e.resolveUpstreamModel(req.Model, auth)
+	if modelOverride != "" {
 		translated = e.overrideModel(translated, modelOverride)
 	}
 	translated = applyPayloadConfigWithRoot(e.cfg, req.Model, to.String(), "", translated)
 	translated = applyReasoningEffortMetadata(translated, req.Metadata, req.Model, "reasoning_effort")
 	upstreamModel := util.ResolveOriginalModel(req.Model, req.Metadata)
-	if upstreamModel != "" {
+	if upstreamModel != "" && modelOverride == "" {
 		translated, _ = sjson.SetBytes(translated, "model", upstreamModel)
 	}
 	translated = normalizeThinkingConfig(translated, upstreamModel)
diff --git a/internal/runtime/executor/payload_helpers.go b/internal/runtime/executor/payload_helpers.go
index 222c6e37..b791dac7 100644
--- a/internal/runtime/executor/payload_helpers.go
+++ b/internal/runtime/executor/payload_helpers.go
@@ -52,10 +52,14 @@ func applyReasoningEffortMetadata(payload []byte, metadata map[string]any, model
 	if len(metadata) == 0 {
 		return payload
 	}
-	if !util.ModelSupportsThinking(model) {
+	if field == "" {
 		return payload
 	}
-	if field == "" {
+	baseModel := util.ResolveOriginalModel(model, metadata)
+	if baseModel == "" {
+		baseModel = model
+	}
+	if !util.ModelSupportsThinking(baseModel) && !util.IsOpenAICompatibilityModel(baseModel) {
 		return payload
 	}
 	if effort, ok := util.ReasoningEffortFromMetadata(metadata); ok && effort != "" {
@@ -239,6 +243,9 @@ func normalizeThinkingConfig(payload []byte, model string) []byte {
 	}
 
 	if !util.ModelSupportsThinking(model) {
+		if util.IsOpenAICompatibilityModel(model) {
+			return payload
+		}
 		return stripThinkingFields(payload, false)
 	}
 
diff --git a/internal/util/thinking.go b/internal/util/thinking.go
index 9671f20b..793134fc 100644
--- a/internal/util/thinking.go
+++ b/internal/util/thinking.go
@@ -25,33 +25,33 @@ func ModelSupportsThinking(model string) bool {
 // or min (0 if zero is allowed and mid <= 0).
 func NormalizeThinkingBudget(model string, budget int) int {
 	if budget == -1 { // dynamic
-		if found, min, max, zeroAllowed, dynamicAllowed := thinkingRangeFromRegistry(model); found {
+		if found, minBudget, maxBudget, zeroAllowed, dynamicAllowed := thinkingRangeFromRegistry(model); found {
 			if dynamicAllowed {
 				return -1
 			}
-			mid := (min + max) / 2
+			mid := (minBudget + maxBudget) / 2
 			if mid <= 0 && zeroAllowed {
 				return 0
 			}
 			if mid <= 0 {
-				return min
+				return minBudget
 			}
 			return mid
 		}
 		return -1
 	}
-	if found, min, max, zeroAllowed, _ := thinkingRangeFromRegistry(model); found {
+	if found, minBudget, maxBudget, zeroAllowed, _ := thinkingRangeFromRegistry(model); found {
 		if budget == 0 {
 			if zeroAllowed {
 				return 0
 			}
-			return min
+			return minBudget
 		}
-		if budget < min {
-			return min
+		if budget < minBudget {
+			return minBudget
 		}
-		if budget > max {
-			return max
+		if budget > maxBudget {
+			return maxBudget
 		}
 		return budget
 	}
@@ -105,3 +105,16 @@ func NormalizeReasoningEffortLevel(model, effort string) (string, bool) {
 	}
 	return "", false
 }
+
+// IsOpenAICompatibilityModel reports whether the model is registered as an OpenAI-compatibility model.
+// These models may not advertise Thinking metadata in the registry.
+func IsOpenAICompatibilityModel(model string) bool {
+	if model == "" {
+		return false
+	}
+	info := registry.GetGlobalRegistry().GetModelInfo(model)
+	if info == nil {
+		return false
+	}
+	return strings.EqualFold(strings.TrimSpace(info.Type), "openai-compatibility")
+}
diff --git a/internal/watcher/watcher.go b/internal/watcher/watcher.go
index 1f4f9043..f321a7c9 100644
--- a/internal/watcher/watcher.go
+++ b/internal/watcher/watcher.go
@@ -14,6 +14,7 @@ import (
 	"os"
 	"path/filepath"
 	"reflect"
+	"runtime"
 	"sort"
 	"strings"
 	"sync"
@@ -61,6 +62,7 @@ type Watcher struct {
 	reloadCallback    func(*config.Config)
 	watcher           *fsnotify.Watcher
 	lastAuthHashes    map[string]string
+	lastRemoveTimes   map[string]time.Time
 	lastConfigHash    string
 	authQueue         chan<- AuthUpdate
 	currentAuths      map[string]*coreauth.Auth
@@ -127,8 +129,9 @@ type AuthUpdate struct {
 const (
 	// replaceCheckDelay is a short delay to allow atomic replace (rename) to settle
 	// before deciding whether a Remove event indicates a real deletion.
-	replaceCheckDelay    = 50 * time.Millisecond
-	configReloadDebounce = 150 * time.Millisecond
+	replaceCheckDelay        = 50 * time.Millisecond
+	configReloadDebounce     = 150 * time.Millisecond
+	authRemoveDebounceWindow = 1 * time.Second
 )
 
 // NewWatcher creates a new file watcher instance
@@ -721,8 +724,9 @@ func (w *Watcher) authFileUnchanged(path string) (bool, error) {
 	sum := sha256.Sum256(data)
 	curHash := hex.EncodeToString(sum[:])
 
+	normalized := w.normalizeAuthPath(path)
 	w.clientsMutex.RLock()
-	prevHash, ok := w.lastAuthHashes[path]
+	prevHash, ok := w.lastAuthHashes[normalized]
 	w.clientsMutex.RUnlock()
 	if ok && prevHash == curHash {
 		return true, nil
@@ -731,19 +735,63 @@ func (w *Watcher) authFileUnchanged(path string) (bool, error) {
 }
 
 func (w *Watcher) isKnownAuthFile(path string) bool {
+	normalized := w.normalizeAuthPath(path)
 	w.clientsMutex.RLock()
 	defer w.clientsMutex.RUnlock()
-	_, ok := w.lastAuthHashes[path]
+	_, ok := w.lastAuthHashes[normalized]
 	return ok
 }
 
+func (w *Watcher) normalizeAuthPath(path string) string {
+	trimmed := strings.TrimSpace(path)
+	if trimmed == "" {
+		return ""
+	}
+	cleaned := filepath.Clean(trimmed)
+	if runtime.GOOS == "windows" {
+		cleaned = strings.TrimPrefix(cleaned, `\\?\`)
+		cleaned = strings.ToLower(cleaned)
+	}
+	return cleaned
+}
+
+func (w *Watcher) shouldDebounceRemove(normalizedPath string, now time.Time) bool {
+	if normalizedPath == "" {
+		return false
+	}
+	w.clientsMutex.Lock()
+	if w.lastRemoveTimes == nil {
+		w.lastRemoveTimes = make(map[string]time.Time)
+	}
+	if last, ok := w.lastRemoveTimes[normalizedPath]; ok {
+		if now.Sub(last) < authRemoveDebounceWindow {
+			w.clientsMutex.Unlock()
+			return true
+		}
+	}
+	w.lastRemoveTimes[normalizedPath] = now
+	if len(w.lastRemoveTimes) > 128 {
+		cutoff := now.Add(-2 * authRemoveDebounceWindow)
+		for p, t := range w.lastRemoveTimes {
+			if t.Before(cutoff) {
+				delete(w.lastRemoveTimes, p)
+			}
+		}
+	}
+	w.clientsMutex.Unlock()
+	return false
+}
+
 // handleEvent processes individual file system events
 func (w *Watcher) handleEvent(event fsnotify.Event) {
 	// Filter only relevant events: config file or auth-dir JSON files.
 	configOps := fsnotify.Write | fsnotify.Create | fsnotify.Rename
-	isConfigEvent := event.Name == w.configPath && event.Op&configOps != 0
+	normalizedName := w.normalizeAuthPath(event.Name)
+	normalizedConfigPath := w.normalizeAuthPath(w.configPath)
+	normalizedAuthDir := w.normalizeAuthPath(w.authDir)
+	isConfigEvent := normalizedName == normalizedConfigPath && event.Op&configOps != 0
 	authOps := fsnotify.Create | fsnotify.Write | fsnotify.Remove | fsnotify.Rename
-	isAuthJSON := strings.HasPrefix(event.Name, w.authDir) && strings.HasSuffix(event.Name, ".json") && event.Op&authOps != 0
+	isAuthJSON := strings.HasPrefix(normalizedName, normalizedAuthDir) && strings.HasSuffix(normalizedName, ".json") && event.Op&authOps != 0
 	if !isConfigEvent && !isAuthJSON {
 		// Ignore unrelated files (e.g., cookie snapshots *.cookie) and other noise.
 		return
@@ -761,6 +809,10 @@ func (w *Watcher) handleEvent(event fsnotify.Event) {
 
 	// Handle auth directory changes incrementally (.json only)
 	if event.Op&(fsnotify.Remove|fsnotify.Rename) != 0 {
+		if w.shouldDebounceRemove(normalizedName, now) {
+			log.Debugf("debouncing remove event for %s", filepath.Base(event.Name))
+			return
+		}
 		// Atomic replace on some platforms may surface as Rename (or Remove) before the new file is ready.
 		// Wait briefly; if the path exists again, treat as an update instead of removal.
 		time.Sleep(replaceCheckDelay)
@@ -978,7 +1030,8 @@ func (w *Watcher) reloadClients(rescanAuth bool, affectedOAuthProviders []string
 				if !info.IsDir() && strings.HasSuffix(strings.ToLower(info.Name()), ".json") {
 					if data, errReadFile := os.ReadFile(path); errReadFile == nil && len(data) > 0 {
 						sum := sha256.Sum256(data)
-						w.lastAuthHashes[path] = hex.EncodeToString(sum[:])
+						normalizedPath := w.normalizeAuthPath(path)
+						w.lastAuthHashes[normalizedPath] = hex.EncodeToString(sum[:])
 					}
 				}
 				return nil
@@ -1025,6 +1078,7 @@ func (w *Watcher) addOrUpdateClient(path string) {
 
 	sum := sha256.Sum256(data)
 	curHash := hex.EncodeToString(sum[:])
+	normalized := w.normalizeAuthPath(path)
 
 	w.clientsMutex.Lock()
 
@@ -1034,14 +1088,14 @@ func (w *Watcher) addOrUpdateClient(path string) {
 		w.clientsMutex.Unlock()
 		return
 	}
-	if prev, ok := w.lastAuthHashes[path]; ok && prev == curHash {
+	if prev, ok := w.lastAuthHashes[normalized]; ok && prev == curHash {
 		log.Debugf("auth file unchanged (hash match), skipping reload: %s", filepath.Base(path))
 		w.clientsMutex.Unlock()
 		return
 	}
 
 	// Update hash cache
-	w.lastAuthHashes[path] = curHash
+	w.lastAuthHashes[normalized] = curHash
 
 	w.clientsMutex.Unlock() // Unlock before the callback
 
@@ -1056,10 +1110,11 @@ func (w *Watcher) addOrUpdateClient(path string) {
 
 // removeClient handles the removal of a single client.
 func (w *Watcher) removeClient(path string) {
+	normalized := w.normalizeAuthPath(path)
 	w.clientsMutex.Lock()
 
 	cfg := w.config
-	delete(w.lastAuthHashes, path)
+	delete(w.lastAuthHashes, normalized)
 
 	w.clientsMutex.Unlock() // Release the lock before the callback
 
diff --git a/sdk/auth/iflow.go b/sdk/auth/iflow.go
index a240b431..ee96bdaa 100644
--- a/sdk/auth/iflow.go
+++ b/sdk/auth/iflow.go
@@ -107,7 +107,7 @@ func (a *IFlowAuthenticator) Login(ctx context.Context, cfg *config.Config, opts
 		return nil, fmt.Errorf("iflow authentication failed: missing account identifier")
 	}
 
-	fileName := fmt.Sprintf("iflow-%s.json", email)
+	fileName := fmt.Sprintf("iflow-%s-%d.json", email, time.Now().Unix())
 	metadata := map[string]any{
 		"email":         email,
 		"api_key":       tokenStorage.APIKey,