Engine light on cause gas cap, it continues appearing, what to do? on 1996 Pontiac Sunfire

I change the gas cap, fix, tighten fix, but continuos appearing, I continue resetting the code any solutions.

1 answer
The EVAP system needs to be tested, The information the computer is receiving from the test is not holding a preset tolerance for a properly sealed system. It is recognizing there must be a gas cap issue because of the information it has received is a very large leak. Obviously it's not the gas cap.