Always Being Asked to Confirm My Email Address and Phone Number.

Every time I sign in to read my Xfinity email I get a request to confirm my personal email address and mobile phone number. And each time I click 'Looks good,' but the very next time I sign in to read my email, the same request is there. How can I stop this request from appearing?

Please note:

I allow cookies on the *.xfinity.com domain.

The same issue happens on Google Chrome, Microsoft Edge and Mozilla Firefox.