Hello princess_02,
Thank you for reaching out in Apple Support Communities. Have you restarted your Mac to see if the notifications for the banner continue to appear for FaceTime? This is a step that can help resolve unexpected behavior. If needed, here's how: Shut down or restart your Mac - Apple Support
Now if a restart was performed, we recommend to restart your Mac in safe mode. This is a step that can help clear out some caches on your Mac. Once you're in safe mode, please restart the Mac as normal and test to see if that helps. Here's how to restart a Mac in safe mode:
Start up your Mac with Apple silicon in safe mode
1. On your Mac, choose Apple menu
> Shut Down.
2. Wait for your Mac to shut down completely. A Mac is completely shut down when the screen is black and any lights (including in the Touch Bar) are off.
3. Press and hold the power button on your Mac until “Loading startup options” appears.
4. Select a volume.
5. Press and hold the Shift key, then click Continue in Safe Mode.
6. The computer restarts automatically. When the login window appears, you should see “Safe Boot” in the menu bar.
These steps are outlined here: Start up your Mac in safe mode - Apple Support
Kind regards.