Sign-in isn’t wired up on this server process yet (SUPABASE_ANON_KEY is blank after load). Paste the Supabase anon public key (API settings) after SUPABASE_ANON_KEY= in the .env next to server.js, then save the file and restart the Node process (npm start / PM2). If it still shows this banner, verify the shell isn’t overriding with an empty variable (env | grep SUPABASE). On some hosts dotenv skips keys that exist as SUPABASE_ANON_KEY=; the server clears blank SUPABASE_* before loading .env.