I got message “One standard license is valid only for 1 website. Running multiple websites on a single license is a copyright violation. When moving a site from one domain to another please deactivate theme first.”
But I haven’t another domain or website, how to deactivate?
It could be 3 reasons of the problem:
1) You did not activate theme using the purchase code
2) Conflict with some third-party plugin that you also installed that change the link to the plugins installation page. Do you have access to Appearance > Install Plugins?
3) Your user has limited permissions
If it does not help provide me temporary Dashboard and FTP access to your site to check.