Apple TV+ streaming service is frozen…

When I recently tried to launch AppleTV+ from my Xfinity stb, I was presented with an authorization screen with two options: 1) Cancel or 2) sign-in. I chose “cancel” and now I’m frozen out.

Now after 2 days, I can get to the frozen Apple TV+ logo and nothing happens. Zilch.

How can I get the application to let me authenticate?

thanks!