diff --git a/src/api/client.ts b/src/api/client.ts
index cc2b423..9dcdc85 100644
--- a/src/api/client.ts
+++ b/src/api/client.ts
@@ -64,26 +64,47 @@ export const apiClient = axios.create({
   },
 });
 
+// Auth endpoints that don't need Bearer token or token refresh
+const AUTH_ENDPOINTS = [
+  '/cabinet/auth/telegram',
+  '/cabinet/auth/telegram/widget',
+  '/cabinet/auth/email/login',
+  '/cabinet/auth/email/register',
+  '/cabinet/auth/email/verify',
+  '/cabinet/auth/refresh',
+  '/cabinet/auth/password/forgot',
+  '/cabinet/auth/password/reset',
+];
+
+function isAuthEndpoint(url: string | undefined): boolean {
+  if (!url) return false;
+  return AUTH_ENDPOINTS.some((endpoint) => url.includes(endpoint));
+}
+
 // Request interceptor - add auth token with expiration check
 apiClient.interceptors.request.use(async (config: InternalAxiosRequestConfig) => {
-  let token = tokenStorage.getAccessToken();
+  // Skip token refresh and Bearer header for auth endpoints
+  // These endpoints authenticate via init_data/credentials, not Bearer tokens
+  if (!isAuthEndpoint(config.url)) {
+    let token = tokenStorage.getAccessToken();
 
-  // Проверяем срок действия токена перед запросом
-  if (token && isTokenExpired(token)) {
-    // Используем централизованный менеджер для refresh
-    const newToken = await tokenRefreshManager.refreshAccessToken();
-    if (newToken) {
-      token = newToken;
-    } else {
-      // Refresh не удался - редирект на логин
-      tokenStorage.clearTokens();
-      safeRedirectToLogin();
-      return config;
+    // Проверяем срок действия токена перед запросом
+    if (token && isTokenExpired(token)) {
+      // Используем централизованный менеджер для refresh
+      const newToken = await tokenRefreshManager.refreshAccessToken();
+      if (newToken) {
+        token = newToken;
+      } else {
+        // Refresh не удался - редирект на логин
+        tokenStorage.clearTokens();
+        safeRedirectToLogin();
+        return config;
+      }
     }
-  }
 
-  if (token && config.headers) {
-    config.headers.Authorization = `Bearer ${token}`;
+    if (token && config.headers) {
+      config.headers.Authorization = `Bearer ${token}`;
+    }
   }
 
   const telegramInitData = getTelegramInitData();
diff --git a/src/main.tsx b/src/main.tsx
index 05c79a7..6d79dbd 100644
--- a/src/main.tsx
+++ b/src/main.tsx
@@ -4,6 +4,7 @@ import { QueryClient, QueryClientProvider } from '@tanstack/react-query';
 import {
   init,
   restoreInitData,
+  retrieveRawInitData,
   mountMiniApp,
   miniAppReady,
   mountThemeParams,
@@ -19,6 +20,7 @@ import {
   requestFullscreen,
   isFullscreen,
 } from '@telegram-apps/sdk-react';
+import { clearStaleSessionIfNeeded } from './utils/token';
 import { AppWithNavigator } from './AppWithNavigator';
 import { ErrorBoundary } from './components/ErrorBoundary';
 import { initLogoPreload } from './api/branding';
@@ -37,6 +39,9 @@ if (!alreadyInitialized) {
     init();
     restoreInitData();
 
+    // Сбрасываем старые токены если init data изменился (новая сессия Telegram)
+    clearStaleSessionIfNeeded(retrieveRawInitData() || null);
+
     // Mount components — each in its own try/catch so one failure doesn't block others
     try {
       mountMiniApp();
diff --git a/src/pages/Login.tsx b/src/pages/Login.tsx
index 3a3669a..76b9f3b 100644
--- a/src/pages/Login.tsx
+++ b/src/pages/Login.tsx
@@ -24,7 +24,13 @@ export default function Login() {
   const navigate = useNavigate();
   const location = useLocation();
   const [searchParams] = useSearchParams();
-  const { isAuthenticated, loginWithTelegram, loginWithEmail, registerWithEmail } = useAuthStore();
+  const {
+    isAuthenticated,
+    isLoading: isAuthInitializing,
+    loginWithTelegram,
+    loginWithEmail,
+    registerWithEmail,
+  } = useAuthStore();
 
   // Extract referral code from URL
   const referralCode = searchParams.get('ref') || '';
@@ -111,7 +117,12 @@ export default function Login() {
   }, [isAuthenticated, navigate, getReturnUrl]);
 
   // Try Telegram WebApp authentication on mount (with auto-retry on 401)
+  // Wait for auth store initialization to complete to avoid race conditions
+  // with stale tokens triggering interceptor refresh/redirect loops
   useEffect(() => {
+    // Don't attempt Telegram auth until store initialization is done
+    if (isAuthInitializing) return;
+
     const tryTelegramAuth = async () => {
       const initData = getTelegramInitData();
       if (!isInTelegramWebApp() || !initData) return;
@@ -126,15 +137,18 @@ export default function Login() {
           navigate(getReturnUrl(), { replace: true });
           return;
         } catch (err) {
-          const status = (err as { response?: { status?: number } })?.response?.status;
-          console.warn(`Telegram auth attempt ${attempt + 1} failed with status:`, status);
+          const error = err as { response?: { status?: number; data?: { detail?: string } } };
+          const status = error.response?.status;
+          const detail = error.response?.data?.detail;
+          console.warn(`Telegram auth attempt ${attempt + 1} failed:`, status, detail);
 
           if (status === 401 && attempt < MAX_RETRIES) {
             await new Promise((r) => setTimeout(r, 1500));
             continue;
           }
 
-          setError(t('auth.telegramRequired'));
+          // Show backend error detail if available, otherwise generic message
+          setError(detail || t('auth.telegramRequired'));
         }
       }
 
@@ -142,7 +156,7 @@ export default function Login() {
     };
 
     tryTelegramAuth();
-  }, [loginWithTelegram, navigate, t, getReturnUrl]);
+  }, [isAuthInitializing, loginWithTelegram, navigate, t, getReturnUrl]);
 
   // Manual retry for Telegram Mini App auth
   const handleRetryTelegramAuth = async () => {
@@ -158,9 +172,14 @@ export default function Login() {
       await loginWithTelegram(initData);
       navigate(getReturnUrl(), { replace: true });
     } catch (err) {
-      const status = (err as { response?: { status?: number } })?.response?.status;
-      console.warn('Telegram auth retry failed with status:', status);
-      setError(t('auth.telegramRetryFailed', 'Authorization failed. Close the app and try again.'));
+      const error = err as { response?: { status?: number; data?: { detail?: string } } };
+      const status = error.response?.status;
+      const detail = error.response?.data?.detail;
+      console.warn('Telegram auth retry failed:', status, detail);
+      setError(
+        detail ||
+          t('auth.telegramRetryFailed', 'Authorization failed. Close the app and try again.'),
+      );
     } finally {
       setIsLoading(false);
     }
diff --git a/src/utils/token.ts b/src/utils/token.ts
index cf5e483..9ce503a 100644
--- a/src/utils/token.ts
+++ b/src/utils/token.ts
@@ -152,6 +152,25 @@ export const tokenStorage = {
   },
 };
 
+export function clearStaleSessionIfNeeded(freshInitData: string | null): void {
+  if (!freshInitData) return;
+
+  try {
+    const stored = sessionStorage.getItem(TOKEN_KEYS.TELEGRAM_INIT);
+
+    if (stored && stored !== freshInitData) {
+      sessionStorage.removeItem(TOKEN_KEYS.ACCESS);
+      sessionStorage.removeItem(TOKEN_KEYS.REFRESH);
+      sessionStorage.removeItem(TOKEN_KEYS.USER);
+    }
+
+    sessionStorage.setItem(TOKEN_KEYS.TELEGRAM_INIT, freshInitData);
+    localStorage.removeItem(TOKEN_KEYS.TELEGRAM_INIT);
+  } catch {
+    // Storage недоступен
+  }
+}
+
 /**
  * Централизованный менеджер обновления токенов
  * Предотвращает множественные параллельные refresh запросы