User is unable to log in to Signals Notebook, getting "You need a license to access this application".
Solution:
Tenant administrator can try deactivating and reactivating the affected user. Go to "System Configuration" >> "Users" >> "Action" column >> click "Remove user" as shown on the image below.
Once deactivated, go to the "Deleted" tab on the "Users" page. In the "Action" column, click "Reactivate user" as shown on the image below. After doing this, please ask the user to try to log in again.
If it doesn't fix the issue, please don't hesitate to contact Support.