There are four ways to resolve problems with a Mac.
1) Turn it off and back on.
2) When powering on, do a PRAM reset (holding down the Command, Option, P, and R keys together and wait for the second start-up sound before releasing).
3) Before powering up, do a SMC reset (holding down the Command, Shift, Option, and power keys together for 10 seconds, then release and press power again to start up).
4) Delete and reinstall the problematical app.
If any of these fail to resolve the problem, try to isolate the source of the problem by logging in with a different account to see if the problem exists with the system or the individual account. Then call Apple support to have them help find the problem. A worst case scenario to resolve a system-related problem is to re-install the OS. A worst case scenario to resolve a user login related problem is to delete that login and recreate it from a Time Machine backup selecting only documents, music, and photos to be restored.
This should not be considered as a full analysis or troubleshooting procedure. However, if your Mac appears to be sluggish, either a PRAM reset or a SMC reset or both can restore performance.
John R Carter Sr