If you're experiencing issues with Google Chat notifications not working, you can try the following troubleshooting steps:

Check notification settings: Make sure that notifications are enabled for Google Chat on your device. To do this:

On Android: Go to Settings > Apps & Notifications > Google Chat > Notifications. Ensure that notifications are enabled.
On iOS: Go to Settings > Notifications > Google Chat. Ensure that notifications are allowed.
Restart the device: Sometimes a simple restart can resolve notification issues. Restart your device and check if the notifications start working again.

Clear cache (Android): Clearing the cache of the Google Chat app can help resolve notification problems. Here's how:

Go to Settings > Apps & Notifications > Google Chat.
Tap on "Storage & Cache" or "Storage" (depending on your device).
Tap "Clear Cache" and confirm the action.
Restart the app and see if the notifications are functioning now.
Check battery optimization settings (Android): Some devices have battery optimization features that may interfere with app notifications. To ensure Google Chat is not being optimized excessively:

Go to Settings > Battery > Battery Optimization (or a similar option).
Search for Google Chat in the list and select "Don't Optimize" or "No Restrictions" to prevent it from being excessively optimized.
Update the app: Ensure that you have the latest version of Google Chat installed on your device. Outdated versions may have bugs or compatibility issues that affect notifications. Visit your device's app store (Google Play Store or Apple App Store) and check for any available updates for Google Chat.

Disable Do Not Disturb mode: Check if your device's Do Not Disturb mode is enabled, as it can suppress notifications. Disable it or configure it to allow Google Chat notifications to come through.

Reinstall the app: If the issue persists, uninstall Google Chat from your device and then reinstall it from the app store. This can help resolve any underlying app-related problems.

Check for system updates: Ensure that your device's operating system is up to date. System updates often include bug fixes and improvements that can address notification issues.

Contact support: If none of the above steps work, consider reaching out to Google Chat support for further assistance. They may have specific troubleshooting steps or be able to investigate the issue on their end.

By following these steps, you should be able to troubleshoot and fix the Google Chat notification not working problem on your device.