Unable to withdraw

I cant make a withdrawal. They asked me to deposit a lot of money into my account with several reasons.1. They asked me to deposit of 1350 USDT to verify i am the owner of my account. 2. They asked me deposit 2000 usdt for supervision Department. 3. They asked to deposit 9500usdt to upgrade my account to Vip. 4. They asked me to deposit 5000 usdt to verify my account again. I have deposited almost 40,000 usdt into their platform.