Hey there! Sorry to read about these phantom notifications -- that's super weird! When they pop up, are they specifically notifying you of emails or messages -- or do they come in for other apps even though your settings are disabled?
Are you still getting the phantom notifications on your phone? If so, I'd like to have you try running your phone in Safe Mode. This will let us know if an app is interfering with the notifications. One other thing that may be going on is the Accessibility settings and turn off tone reminder. Give that a shot and let me know how it goes.
Just wanted to check in once more!