Your subscription license is tied with the google account that you purchased the license with.
For the extension to be activated with your license, the Chrome browser needs to be signed in with the same google account.
1. Confirm activation status
Look at the LICENSE mark on extension's popup window.
If it is green then the extension is activated with valid license.
If it is gray then the extension is not activated.
2. Confirm your chrome browser is signed in with the right google account
Please confirm that your chrome browser is signed in with the google account that you have purchased the license with.
If it is signed in with the right account and still your extension is not activated, please try signing out and back in.
Exporting the data for backup before signing out is highly recommended.
Sometimes rebooting the Chrome browser or machine solves this problem.
3. Confirm your license status
You can confirm your subscription license status at https://payments.google.com/.
Please check you have valid subscription license.