I suggest you to follow these steps:
1. Recheck the Antivirus on your computer if it has a firewall functionality, and check the Windows firewall if you are using windows OS, it could be that the firewall on your OS blocks the connection to our activation server.
2. Please check the firewall on your router, you may have to disable it to activate the license.
3. Please try different internet browsers and be sure that the browser is up to date.