Bug in the the latest update:
Ever since the latest update (June 2020 update) the messages I receive get cut off by the bottom bar of the Messages app. This has never happened before. I now have to scroll up in order to see the newest message.
One UI version 2.1
Do you experience these symptoms if you test your device in safe mode?
If your phone is misbehaving, it's possible that a third-party app is causing the issue. To figure out what app is acting funny, you can use the Safe Mode feature. In Safe Mode, your phone won't run any third-party apps. This allows you to easily identity and remove the app that may be causing the problem.
Give this link a try to test your device in safe mode: