Not able to login from android phone

i am using the blog post sample from here Call a Protected API from a .NET MAUI App
i was able to have that work on my windows desktop with no error.

i then allowed my phone to do usb debug and tried to run the app on my phone.
the app deploys. starts up and i can click the login button.
the browser page to login is shown but after i enter the password the browser winbdow just sits and does not close and i see no error message. in the auth0 dashboard i cant see anything to help me at this point.
i am sure that i am entering the valid password and user info.
but i am new to dotnet maui and to developing for the phone.
where to even look for a clue ?