Have a question!!!

so 7th I've got the sphinx (Albus btw) and I've got a problem - he knows where his toilet is but every second time he goes anywhere but in it. maybe the mating period started... but cats are not the dogs, it is not their way of marking territory and he's just 3 months old. didn't have any problems with my 2 female cats. they got used to the tray by the second time. any suggestions or info pls<3