TM9 said I need to make a 'final payment' of $3,000 before withdrawing.

They told me that before I can Futures trading platform app downloadwithdraw my funds, I need to pay a “final payment” of $3,000. I was never informed about this fee when I first signed up, and it seems to have appeared out of nowhere. This is highly suspicious, and I feel like they are just finding new ways to delay the withdrawal process and take more money from me. Has anyone else been asked for a "final payment"? Should I pay this fee, or is this just a scam to hold my funds?