this is how the slots work , sadly
the variance can be disastrous and you could be losing deposit after deposit without hitting a 100x or a jackpot
some game manufacturers have a smoother curve , others pay rarely but in big chunks ( Microgaming , for example ) but in general , they should return around 97-98% on average
I witnessed long ass losing sessions on jamming jars , but on the other hand I saw people win 15-20k euros playing it relatively low stakes
could be a really bad unlucky streak , 200k is nothing to be sneezing at its big money I hope you recover it with your next deposits