I have a valid license for a legacy version

Hi
I got a new Mac and transferred all my data with the migration assistant. If I open up parallels it says that my license is used. If I then klick "activate on this Mac" I get the response, that the product license cannot be confirmed and that I reached the maximum amount of activations for this activation key. I've first deactivated the version on my old Mac.
I am using a Parallels 11 Version for this Mac.

 

Hi, we've reset your Parallels Desktop 11 license key, please check the issue.