You may have installed a fake 'utility' called 'Advanced Mac Cleaner.' Like any software that purports to automatically 'clean up' or 'speed up' a Mac, it's a scam, and some variants of it are ad-injection malware. That's how you create problems, not how you solve them. First, never use any kind of 'anti-virus' or 'anti-malware' software on a Mac.
