BahseGel Max Win Rule Wiped Out My Winnings

I put money into the Bahsegel website and got a 400 TL bonus, which meant that my money had doubled. I was so excited when I played Sugar Rush and won 30,000 coins. But, to my disappointment, the Max Win rule took away all 30,000 TL that I had won. I called customer service and was told that they would only pay out 5 times the amount of the bonus. I feel completely cheated and angry. Why give bonuses if you can't get the most out of them? This is just crazy! Can someone help me deal with this? Thank you so much for your support.