Check and clean your clipboard using service widget shortcut and quick setting tile.

Source Code: https://github.com/DeweyReed/ClipboardCleaner

Possible reasons for the app failure
1. From Android 10(Q) Non-input-method apps can't get modify and listen to the clipboard in the background. Your phone is safer and doesn't need this app anymore.
2. If you're seeing multiple clips or the clip history it means something like a soft keyboard app stores them. In this case this app fails.