Notification no longer working

I am a new Hubitat user. I set up the notifications app. I have a Schlage lock that I set to notify me when the lock was unlocked and when it was locked. Notifications are set to go to an iPhone12 with current iOS. All was working perfectly for several days. Starting yesterday I am no longer getting any notifications. When I go into the app on the iphone / Notifications, I get the following error message - "Device ID xxxxxx-xxxx-xxxxx-xxxxx with token is not valid or expired." I have rebooted the iphone and verified in Hub that all is set up properly - ie, nothing changed since I first set up the notifications. Any thoughts on how to solve

Try removing app On phone, .reinstalling and setup your phone as notification device again.

Log out of the app then log back in. It will prompt to create a new device. Don't. This should refresh the token.

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