Hi
1. Clear data of Phone Manager App and then force stop it and check if problem remains or not?
2. If it didn't worked clear cache of all apps with sd maid accessibility service and turn off device then go to recovery menu and clear cache partition and then clear data of phone Manager App.
3. If it didn't work uninstall recent system apps updates like android system webview, YouTube, play services, play store l, themes, huawei related system apps like maps api and HMS and then do what i wrote in number 2.
Hope it helps.
Good luck