diff --git a/frontend/src/api/client.ts b/frontend/src/api/client.ts
index ae5515f..bff62c0 100644
--- a/frontend/src/api/client.ts
+++ b/frontend/src/api/client.ts
@@ -47,6 +47,16 @@ export function setValidationErrorHandler(handler: (errors: Record<string, strin
 
 apiClient.interceptors.request.use(
   (config: InternalAxiosRequestConfig) => {
+    // Normalize URLs: strip a redundant leading '/api/v1' when it collides
+    // with the axios baseURL '/api/v1' (double-prefix → 404/405). Done here
+    // in the interceptor (not only in the apiX wrappers) so DIRECT apiClient
+    // calls are covered too — stale browser-cache chunks keep calling with
+    // full prefixes after deploys and this heals them transparently.
+    if (typeof config.url === 'string' && config.url.startsWith('/api/v1/')) {
+      config.url = config.url.slice('/api/v1'.length);
+    } else if (config.url === '/api/v1') {
+      config.url = '/';
+    }
     // Attach CSRF token on unsafe methods
     const unsafe = ['post', 'put', 'patch', 'delete'];
     if (unsafe.includes(config.method?.toLowerCase() ?? '') && csrfToken) {