I've been seeing a lot of posts lately about accounts being frozen, and I feel for you merchants. I'll share what I understand about account issues. There are two cases where an account can be frozen:

1. Frozen by the police because it's linked to dirty money. There's nothing you can do to resolve this. The only way to put an end to it is to cut off the source of the funds and cash out. How you cash out is up to you.

2. Frozen by the bank because it suspects the source of the funds, or because that bank doesn't allow P2P. This can happen if you opened your account online and haven't verified your identity in person at a branch. Or if there's an unusually large flow of money, and so on. If the bank freezes your account, go to a branch and they'll handle it. They may either reopen it after you provide proof, or let you withdraw your money and then close the account.

That's all I know, so I hope you can share any additional advice. Oh, and if you come across a merchant like me who makes a bank transfer without a 6-digit code, or tells you that your transfer to me doesn't need a 6-digit code, don't be puzzled. That 6-digit code is just for convenience when checking the transfer; it doesn't matter if you don't have one. Even if I accidentally transfer money to the wrong place, I can still claim a refund as usual.