Need help with my Cubase License Activation!!

I have activated my license for Cubase 10 through eLicenser Control Center (the “Enter Activation Code” button on the top right corner)
However, when I open Cubase 10, it shows “No valid License found”.

And if I enter “Start License Activation” and enter my license, it tells me “The activation code has been used already

:cry: :cry: :cry:
Please tell me what to do!!