2014 Jeep Cherokee - Fob is a stranger

We’re having trouble w/ my son’s Jeep where the car is not recognizing the fob from time to time resulting in alarm going off and/or car not starting. I tried to solve by repairing and replacing the fobs - had the original fobs “cleaned” and reprogrammed and added two new after-market fobs - but still having this problem. Has anyone had success getting this fixed via dealer or other solution?