my iPhone screen says notification canceled and will not do anything. I tried the suggestion for rebooting, but the phone is still stuck

How do I get ride of the screen message "Notification Canceled" on my iPhone 12. My phone randomly started calling emergency #. I was not even touching my phone when it started making a terrible buzzing noise. I chose cancel the call. then the Notification canceled message popped up on my screen. Now I cannot use my phone