Can't reload electric jackhammer

I’m trying to escape from a research facility I started in, but all the doors and windows are made of reinforced glass and steel locked doors. Luckily I was able to find a electric jackhammer in storage but it didn’t have enough UPS fuel left for more than one charge, which I used up trying to find the entrance. I attached a heavy battery mod to it, and it says that disposable heavy batteries are compatible magazines, but all the options to reload it are grayed out. When I try to reload it manually it says I can’t reload the UPS jackhammer +1
Anybody know how to fix this bug?
The roof is way too high up to climb down off of

Yeah, im not know enough of the code to say if its a bug or is intended, but i recall doing something like that a while ago and got the same problem. also dont mod an electric fire starter with a UPS conversion mod, last time i checked, it didnt work.