It's very common for financial institutions to request information about accounts and transactions. It's rare for them to close an account, though. That's usually a bad sign.
You can try to apply pressure by bringing in lawyers and going after the regulator. But that will probably not go anywhere. There are different regulations and guidance notes but in general, financial institutions have no meaningful time limits that they must comply with if an account is closed due to suspicion of money laundering or other financial crime. Innocent clients sometimes get wrongly affected by this.
Most likely, they have identified something suspicious about your account and are currently researching it (you're in a queue of other suspicious accounts and each one takes time to investigate). The most common cause for this is that the account holder has done something that is against the financial institution's terms and conditions.
Your account will probably be permanently closed and in a matter of days or weeks, they will tell you to wire the money out. It's unlikely they will let you keep the account, if it has been this long already. If it takes more than a few days, the case has been escalated to more senior staff and if it goes that far, they almost never decide to keep an account open.
If you don't already have a backup account, start opening several accounts now so you're ready.
