I had experience with the COINBACE exchange, i used it and there were no complaints, only my friend was blocked with a wallet, its not clear what

The usual antifraud system, but in any case, they had to withdraw money to him.

But exchanges may not always make such concessions, some block for free, that is, your money can no longer be withdrawn

If you do not break the rules and do everything honestly, then in fact the chance to get a wallet ban is minimal, and these are rare cases