Open DevTools Network tab and look at the create-conversation response first; the error body names the bad field. Common fix: the persona_id points at a deleted persona or the replica_id is from a different account - copy fresh IDs from the dashboard and retry.

Context: When a Tavus conversation lobby spins on 'Connecting' forever, conversation creation failed (community troubleshooting from the tavus-intake template). Check the browser console for API errors, verify TAVUS_API_KEY is set, and confirm the persona_id/replica_id in the config are real IDs from the dashboard. Also verify camera and mic permissions are granted - HTTPS is required for camera/mic in production.