Hamster ONLY pees on wheel, can’t potty train

Firstly: I KNOW ITS NORMAL FOR HAMSTERS TO PEE ON THE WHEEL.

3 weeks ago I got a dwarf hamster, but they pee EXCLUSIVELY on their wheel, and no where else. I have tried wiping it and putting the scent in the sandbox where I want them to pee, but they completely ignore it. I moved the sandbox to different corners of the cage, but it doesn’t seem to matter where I put it. I’m worried because my last hamster (robo) naturally figured it out, but this time it’s proving to be a lot harder.

I feel like part of it is that this hamster seems a little older, at least a month old and fully grown in size already when I got them from the pet store.

Should I just completely remove the wheel until they can figure it out? I don’t really know what else to do. Thanks