So I am locked with UST on the crypto exchange forever - when placing a sell order for 1 USDT order, they don't execute it, and they don't allow to withdraw it to exchange it with other users
So you lied that you had 100 UST that you offered for exchange or as collateral for a loan? If you can't even withdraw those tokens then you can't exchange them with other members, right?
You really look like a fucking fool now and this only confirms what others have already suspected, that your real intention was to deceive and to scam naive victims.