2012 Jeep Liberty P0441 Code: Is a Loose Gas Cap Really the Cause?

Last week, I had my oil changed on my 2012 Jeep Liberty with 67,000 miles. The service technician added a gas treatment product, which I typically use every 3,000 miles. Shortly after, I received a gas cap warning light. Upon checking, I found the gas cap was not securely tightened. When I re-entered the vehicle, the check engine light also turned on. I’ve been experiencing this issue consistently—each time I check the gas cap, it appears loose even though it clicks into place. After driving a short distance, the cap seems to loosen again. I took the car to AutoZone for diagnostics, where they detected code P0441 and suggested either bad fuel or an engine-related problem. However, they stated that the gas cap itself is not the root cause. I’m skeptical—how can a loose gas cap be ruled out when it consistently fails to stay tight? Should I replace it with an OEM (original equipment manufacturer) gas cap, or does this point to a more serious EVAP system issue such as a faulty purge solenoid, damaged EVAP line, or PCM circuit problem? Any insights or suggestions would be greatly appreciated.