Account activation... associated with another Parallels account

Hi,

I've upgraded my Mac and after installing Parallels, the activation (correctly) says that my license is used on another Mac, but when I try to activate it on the new Mac (hence deactivating it from the old, unavailable Mac), it states (incorrectly) that my license key is associated with another Parallels account.

I checked the key, retrieved the invoice. It's an active key, on the correct account.