Wood Pellets (Questions?)

Hi! I recently switched to wood pellets. I have an adult female cat and a boy kitten and he never liked my normal litter so I was trying alternatives and I’ve really liked this one. Only issue is they only want to pee in it? And neither seem to have used it to poop (I have their other box to be safe!) but I don’t really know why.... I can’t seem to find one that specific about this and I don’t want to keep using the other one with this saw dust thing I tried last (which was stinky) but I want them more comfortable with the pellets besides just their urine.... I’d love any advice with any who are more used to using wood pellets

Changing cat litter can be iffy. Did you switch by mixing the old litter with the new, slowing increasing the new stuff?
I never used wood litter, so I'm afraid that I can't give you any specifics, but I think that your kitties just liked the previous litter better, or they like the idea of using one box for pee and the other one for poop.
I use Yesterday's News, made from the recycled paper. It is very low dust and unscented, but still controlling odor.
Sorry that I can't be of more help!

It’s alright I still appreciate the help!! I’ll try mixing the litter and see