The previous activation key has not been accepted by the license server.

I have bought an upgrade key for Parallel Desktop and try to activate my OS but I couldn't do it and I have gotten the error message following
"
The previous activation key has not been accepted by the license server.
"
Please help me to figure out to activate the machine.

Thanks

 

Hello, we've checked your account jj****sic@gmail.com but didn't find any license key associated with it.
Could you provide us with your license key please?

 

Dear Maria. I face a similar trouble. How can I find out, which account ist linked with the license key? I can support you with the license key. How can I send it to you?
Markus

 

Hello, please reply me back via the private message.