Withdrawal has been not allowed.

I applied to withdraw on Sep 2nd, but the platform asked me to pay the deposit. And later, it asked me to pay the commission for the bank and the third party deposit. But, I didn't agree to pay the party deposit, then the platform threatened me that it wouldn't handle my application and I would lose all of my money in the account. It's useless to report the broker. The customer service worker just told me that the broker didn't make any response. I had no other solution but to ask the customer service worker to help me to mediate between me and the broker. Please help us, and my money.