You are truly crazy, still spinning a slot that can't be hitting with more than 200-300 spins. My self already change the slot while there is no hitting with around 150-250 spin, I think that's slot is kinda on drain situation.
You should take a break mate, a few days ago on plinko now slot ~XD
RTP is usually down during the first few days of the challenge promotions but this is my personal assumption. The raffle prize and race rewards have to be paid somehow. The way the RTP works differently for each casino now makes more sense in promo days.