Joined Objects, Texture Paint Not Working

I was working on a model with the head separate from the body for a while and finally joined the two after they’d been textured. Upon doing so, texture paint has stopped working on either body part.

Things I have tried:
Reunwrapping the model, reassinging materials, realigning the models in the UV Image Editor window - they weren’t able to be painted, even when they were in spots with color.

The paint bucket works, but that covers up all the other textures that are already there. And even then, the brush doesn’t paint over the newly painted (with the bucket) model.

I’ve been scouring older posts and watching videos, but am unable to find this specific issue so far. I’m including the .blend file, just in case anyone wants to test the issue for themselves. 10_v034.blend (4.9 MB)

I figured out the issue. Apparently, I had a texture selected on the brush that had nothing on it, so it was acting like a stamp that was empty.