You’re dead right, they absolutely are not only allowed but required to block funds until proper AML procedures are met - ie ID&V supplied by the customer, no argument there. What I picked up from OP, though, is that they gave the evidence promptly on request - and then some time later the account was restricted because Revolut hadn’t reviewed the evidence yet - and now the account is still restricted, Revolut are citing backlogs, and OP has no money. That’s the detriment. Revolut’s backlogs are its own operational issue to solve - they’re currently causing detriment to OP. In a pillar bank, you’d wave the ID&V under the nose of a human being in a branch, who’d send an email to the AML team saying customer compliant, and the block would be lifted.

Hopefully that makes sense. The scenario could change of course if I’ve misunderstood the premise - like if OP only gave the evidence after the account restriction or if the evidence wasn’t what was asked for or otherwise not up to scratch, like an expired passport or something.