Fruit flies suddenly around litter box??

I’ve had my cats for 4 years and NEVER had bugs or fruit flies near or in the litter box. I scoop it daily and spray it out/completely wash every 2 weeks. Moved into boyfriend’s house and all of a sudden it’s fruit flies spawning all in the litter boxes and they’re driving me crazyyy. Why is this randomly happening and how can I combat it? I’ve tried cleaning the boxes more often, baking soda, and fly traps right on top of the box and nothing has worked!