I got a Battery Error on one of my MPP batts a while back. All I found out from DJI online help was to run the battery down, and then do a normal recharge. I just turned on the drone and let it run until it turned itself off. That did not work I still got the same error and the MPP would not take off with that battery attached. I did that 3 times all with the same result, the battery charges up to 4-Green but the controller shows the Battery Error message as soon as you try and turn the drone on. It seems to be a small voltage imbalance between the 3 internal cells, when you go in and look at the detailed battery data. I have 2 other good batteries, so I can still fly. I have not looked into getting the ‘bad’ cell replaced. The entire system is about 2 years old, but no DJI Care right now. I would guess that battery has gone through more than a few dozen charge cycles. Good luck on your end, but it sucks big time this happened on your vacation time.