A notification with a heading "Disable harmful app" from something that looks like Google Play (because of the logo). No amount of settings is making it go away
This can be removed in Google Settings.
- Open Settings.
- Select "Google" (if there is no "Google", open Google Settings from your launcher).
- Select "Security".
- Select "Google Play Protect".
- Turn off "Scan device for security threats".
If you don't trust the app you could also uninstall it. Some root apps are flagged as malware (when they are not), but there are also real viruses for Android.