nopara73 (nprofile…zq33) seems to believe that he is on a blacklist, but I think he is not. Here is an alternative explanation:
As you should all already know, exchanges spy on you not only before depositing but also, and even more importantly, after you withdraw from them. That means that if you did something that they don't like, like coinjoining a UTXO that they know was yours, they will close your account.