Money on a crypto exchange, the place where dollars turn into USDT, is held by the exchange. The account has your name on it, but the key is theirs. What you have is a login to their money, held on your behalf. Most days that is a fine deal.
It is also why an exchange can freeze your account in an afternoon. Exchanges are regulated like banks and watched hard, and the cheapest way for them to stay out of trouble is to hold anything that looks doubtful and ask you to explain it. "Under review" can mean days. It often means weeks. Sometimes it means months, a folder of documents proving where every dollar came from, and a support queue with nobody in a hurry at the far end. Meanwhile, that is your rent in there.
This is the sentence Dashing Crypto is built on: if you do not hold the key, you do not own the money. Whoever holds the key does. It is the difference between "my exchange account is under review" and "my exchange account is under review, and my money is at home".
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