Thank you for the reply. I reset the Power Plan license for one of my sites. Still the Messenger update does not appear in the Updates area. I did receive an alert message which said I was logged in by a different account. So I tried my other profile names but nothing worked.

WARNING: You are logged into an UNA.IO account which is different from the account that generated UNA Key & Secret for your domain.

What do you think is wrong? Surely I need to get all of my licenses under one profile. But how?