Message icon shows unread message

Okay, if a simple log-out/in to iCloud did not resolve the problem, I would suggest you again log-out from iCloud, force restart your iPad, then log-in to Cloud.

If this still doesn’t resolve the problem, you might want to raise a case directly with Apple using the Contact Support link at top-right of this page. If you’ve already tried my suggestions, then you’ll be off to a head start with Apple Support.

Do let us know how you get on.

This sometimes happens - I too have experienced it once or twice.

The incorrect count can usually be rectifed by simply logging-out of iCloud, waiting for a momement, then logging back-in to iCloud.

Hope this resolves your issue.

We are talking about Messages - not Mail?

My pleasure to help. Sometimes, it’s a simple fix 🙂