[reconnecting]

I'm not familiar with the exact regulatory text for fintech, but it's highly likely that there is a difference between suspended and closed accounts.

While it may be illegal to close an account without providing proof, it seems possible to soft-block or suspend an account for 'security reasons' without disclosing whether it's related to fraud prevention or other issues.

[mppm]

It's not illegal. Even though having access to banking is absolutely essential to every imaginable business, bank accounts are still treated as a voluntary business relationship by regulators. Some protections exist in the EU for individuals, but for businesses, it is entirely at the discretion of the bank to open and maintain a relationship.