Before this problematic withdrawal, I withdrawn even higher amount a week before without problems, and in older times, I have withdraws of even more, zero problems.
I never do futures or margin, I don't even understand them properly.
Deposit was from another very well known global exchange, and it was not the first. I just subscribed to some earn product on kucoin with the deposit, when product matured, I wanted to withdraw it back to the other exchange, that is it. I did similar things many times. ı don't even spot trade properly on kucoin, I mostly use earn products when I see opportunity
I do not gamble, this is not gamble money or "mixing service" whatever that is.
"Not Your Key, Not Your Coin" has unfortunately played against you here, no one should trust a centralized system for any reason, and I can't imagine myself leaving 50,000 USDT in a single exchange, I don't think I can ever get that mind. My experience with FX brokers has taught me a big lesson in this regard. I rather distribute them in 5 exchanges if the business dealing must pass through exchanges, or else, I prefer to either have my money in my USD bank account or non-custodial crypto wallets where I know that it's indeed my asset.
As it is now, it's stressful, but you should not panic, I believe you will get your money back as long as it's from a legitimate source, it might only take time. Just continue to mount pressure on them and let them know your plan for a legal pursuit if they did not yield, but let this be the last resort plan.
Give them all the necessary documents and scenes required and let's see how it goes. They are using styles like this to scare people, while the faint in heart or those who got their money through illegitimate sources get scared and disappear. Big accounts are often their targets, regardless, they will cough the money out when you are legit, disturbing and determined.