Unable to sign into Facebook app on my iPad 10th Generation

It is a known problem with Facebook on the iPad that Meta has not addressed yet. If you also have Messenger, some users have found success in deleting both apps, then redownloading. First sign into Messenger, then attempt to sign into Facebook.

Install the Facebook Messenger App - and sign-in using your Facebook credentials.

After signing-in to Facebook Messenger, many report that their [previously rejected] credentials are accepted by the Facebook App.

Probably something you've already checked, but make sure that you don't have caps lock or something like that accidentally triggered. If you're sure you're entering the password in correctly, you can try removing and reinstalling the Facebook app and see if that helps. If not, this would be an issue to take up with Facebook support.

Regards.