Cannot access mail on full Zoho One account

Cannot access mail on full Zoho One account

First time trying to access the email app.

When I try to access the app it routes me to the "Add Mobile Number"

I get the message "This mobile number has already been added to your account....."

When I click the link to update the number as login name it routes me to the Two-Factor Authentication which I have already established.

How do I get into email?

Ken