Battery

Until you get your battery disconnect switch: (Assuming you have not completely killed the battery.) Charge it up and just unhook the negative cable when the camper isn’t going to be connected to shore power for days or weeks.

(Somebody may say disconnect the positive side - not sure it matters electrically speaking).

I’ve been “getting to” installing a disconnect switch since 2013 and making due with pulling the negative cable until then...

When the camper won’t be used for long periods I pull the battery out, take it home, and keep it on a tender in my Garage.

So far it’s worked for me. Still on the battery that came with my trailer when new in 2013.

You may want to consider the installation of a battery disconnect switch like this. That will stop those pesky parasitic draws. Check first to make sure your rig doesn't already have such a switch. Make sure you use it whenever you are not using the trailer.

Do you remove the battery after each trip or do you plug the TT in between trips? If not, there are components such as the CO2 detector, fridge circuit board, etc.. that drain your battery over time.

If the RV isn't plugged in, the parasitic draws will kill the battery over time.

Do you have a battery cutoff switch? Or did you otherwise disconnect the battery?