Parallell 11 - Can't transfer license key to new Mac

Good morning,
i can't transfer the license after disconnecting it from the old mac and trying to activate it on the new; I even deleted the software on the old MAC and then tried to remove the .XML file in the preferences. I even tried to activate the demo version an then try the activation from there but it says that I exceed the maximum number of license in use.

Can you please reset the key?
Thanks again in advance.

 

Hi, we've reset your key, please check the issue.

 

I it doesn't help please check this KB article.