Remove the GFI from your supply and use a straight 110-120 outlet for connection to your coach. You have a surge protector for protection which will monitor incoming voltage.
I have a MADP with 8 discharged batteries that sat in a campground over the winter and they had multiple connection problems plus one battery lug that was broken and loose connection of battery cables.
Had to jump start the starter battery's, which would not start coach to get home.
I disconnected 4 of the 8 house batteries and cleaned up all cable connections.
I first used a GFI outlet that my coach was always plugged into but GFI would trip and probably the current draw of 50+ amps on discharged batteries.
I moved the line to a 120 outlet and battery amp levels have now dropped down to 4 to 5 amps after a week of charging and two chassis batteries are at 12.9 v with cord disconnected.
Some times when the fridge is connected a GFI will sense leaking voltage of heating elements for you fridge.
All the red blinking alarms for inverter have now just show normal charge rate.
The charge rate of batteries dropped on its own as batteries charged and three solar panels now read 13.9 on wall display instead of 9.5 when we started charging.
The BCO switch would not operate but now function's correctly.
Batteries before charging were reading 3.5 volts.
More on your
battery systems and you likely have the have the B.M.I. system instead of the Bird system .