Resolve FCM Token Refresh Bug

My web‐based application relies on Firebase Messaging, and the token lifecycle has suddenly gone off the rails. Browsers are no longer registering fresh tokens after a refresh or new login, while the database keeps holding on to stale ones... (Budget: ₹2000 - ₹3500 INR, Jobs: API Integration, Database Management, Debugging, Documentation, Drupal, JavaScript, Web Development)