To activate your Business subscription from App Store, please follow the steps below:

1. First, please check if you are Signed In on App Store with the account used to buy the subscription (to find this info, open App Store, click on Store and see what’s on “View My Account“).
2. Also please make sure you have now on MAC the same Region (the same with Region when you purchase the application from store).
3. Open Project Plan 365 app.
4. Go to menu Help – Subscription and click Restore Business Subscription.
5. Wait for the confirmation message.