My kitten is 6 months old. She had issues with litter training. She was wetting the bed (guest bed) so we started using news paper and stripped the mattress. We transitioned from news paper to litter no problem. I started sleeping in the guest bedroom with her with just sheets. We haven’t had an accident in 2 weeks. Today my wife and I were switching the sheets to the old set (they’ve been washed, we used neutralizer, and we used pheromone spray on them) she immediately had an accident. HELP!