There is no reason to ever run any "cleaning", "optimizing", "speed-up" or anti-virus apps on your Mac. This user tip describes what you need to know and do to protect your Mac: Effective defenses against malware and other threats - Apple Community
Uninstall CleanMyMac according to the developer's instructions.
You can check to see if you've removed all of the files by downloading and running Find Any File to search for any files with the application's name and the developer's name in the file name. For example for CleanMyMac software you'd do the following searches:
1 - Name contains cleanmymac
2 - Name contains macpaw
Any files that are found can be dragged from the search results window to the Desktop or Trash bin in the Dock for deletion.
FAF can search areas that Spotlight can't like invisible folders, system folders and packages.