Mizz, I had a gorgeous kitty that had a pee pee problem.
Took it to the vet, and there were no medical issues found. I did it all. Put the feeding dishes down where it urinated. It even urinated in the garage on plastic bags, not on laundry, or other more popular cat pee pee places that aren’t the litter box.
I cried and said I have to give it away to a farm to be a mouser, or I have to put it down.
The vet said she agreed, some cats can’t be retrained or get it from the git go so they earn a ‘gone’ ticket. I would have been very resentful and angry at the kitty if I’d kept her.
I LOVE kitties, but I love my space without cat elimination more than them.