MacBook Pro - Fake Settings Notification

This has been interesting. Tried to create this message a few minutes ago and it showed up as a red box and while it allowed me to type it claimed I had not entered any test when I tried to send it. What seems to clear/stop temporarily the problem is clearing all history - which I did just before creating this message - which does not have the red box! But doing that all the time is a nuisance. Any suggestions as to how to clear this issue. Unfortunately I installed cleaning and antivirus before - which has now been deleted - but I suspect residues remain in the system. Any suggestions how to permanently stop the problem?