Help fixing this thirst zapper bug

Googled around a bit but could t find anything detailing my specific problem so hopefully someone knows what’s happening.

I use the squirt gun w/Medics to heal NPCs or whatever and that works great, but within my weapon wheel, the thirst zapped is greyed out/displayed as being without ammo. I can select it from the wheel, but can’t do the d-pad quick switch back to it. It’s rare for that to be an actual problem, but as I’m sure everyone knows, you have a 50/50 shot of freezing up if you’re moving while also using the weapon wheel, so it’s definitely a problem sometimes. To be clear, I’m trying to be able to quick-switch between the thirst zapper and whatever other weapon I’m using WITHOUT having to explicitly open the wheel to do so.

This is a problem on two of the three characters I regularly play with, but for some reason not on one of them. The one where it works as intended is human, and the two where it doesn’t are both ghouls, so I’m thinking there’s an issue with the thirst meter maybe so as a ghoul, it’s not reading the water as ammo the same way it does for human characters.

I’ve modded the gun. To and from shooting all the nukas, shot it, reloaded it, ensured it switched back and forth no problem. But when I switch it back to squirt gun the issue rears its head again.

Anybody know if I can fix this somehow? Thanks in advance!