A/C Trips Breaker

We are in the process of moving to California and currently staying in the Flagstaff KOA. Last night and today the A/C has tripped the circuit breaker after being on for a long time and then shutting off. When the A/C tries to come back on it trips the breaker. It isn't tripping the breaker marked A/C either, it is tripping the one marked GFI. We are plugged into shore power with a 50 amp hookup. Any suggestions on how to fix this would be greatly appreciated. We will be living out of the camper for a little while in California and with temperatures going up we need the A/C!!

Note from Admin: Please call Heartland Customer Service on this matter at 877-262-8032