Trailer Brakes Not Staying On

First of all, thanks for all the advice and help. It has been SO helpful! In the end, after replacing the controller, checking the connections, wires, and grounds, I felt there wasn’t much more I could do from the road, so while here in Bend, OR I was able to get a repair shop to look at the hubs. They said the magnets on one side were shorting out, so… hopefully this is really the problem. They are doing a brake job on both sides (plus bearings and some other misc parts it may or may not need), and hopefully this will resolve everything and get us back on the road. We head north tomorrow so my fingers are crossed that this problem is over. Thanks again!