Phone number may be linked to a previous Revolut account

I’m a new US Revolut user, and my current US phone number may be a recycled number that’s still linked to a previous Revolut account.

When I select Create account, I immediately get “Authentication attempt failed.” But if I select Log in, it asks for a passcode I’ve never set up.

I’ve already emailed support@revolut.com, and I can provide proof of number ownership from my carrier, RedPocket, if needed. Has anyone dealt with this, or know the best way to get the number unlinked?