i hope this can fix

frontend/src/api.js

@@ -29,7 +29,7 @@ async function request(method, path, token, body) {
 }
 
 // ═══════════ Auth ═══════════
-export const login = (t, u, p) => request("POST", "/auth/login", null, { username: u, password: p });
+export const login = (username, password) => request("POST", "/auth/login", null, { username, password });
 export const register = (username, email, password) => request("POST", "/auth/register", null, { username, email, password });
 export const getMe = (token) => request("GET", "/auth/me", token);