Hi there pinkmamakat,
It sounds like your Mail notifications are stuck on the right side of your screen for your MacBook Pro. Does restarting your MacBook Pro help? It can refresh the macOS and apps on it, which can help resolve issues like this. If needed, below shows how:
Restart
On your Mac, do any of the following:
* Choose Apple menu
> Restart.
* Press and hold the power button until you see options, then click Restart or press R (or use the Touch Bar).
* If the pointer freezes on the screen or your Mac becomes unresponsive, press and hold Control-Command while you press the power button to force a restart.
* Important: If you force a restart, you may lose unsaved changes in open documents.
If you don’t want the app windows you currently have open to reopen when you restart your Mac and sign in, deselect “Reopen windows when logging back in.”
Those steps are from this article: Log out, sleep, restart, and shut down Mac - Apple Support Please let us know if that helps or if you've already tried that step.
Take care.