Niles Slots Coins Missing

a few days back I closed the game, then reopened it and had 4 thousand less coins. Last night I finished a card, closed the fame with 85,000 coins. Opened it again later and had 79,000 coins. 10X coins gone in a week. Both times this happened, I noticed when I completed a grid on the quest card, it was very slow in loading he collecting. I have no internet issues anywhere.