AT&T Yahoo email Account settings and Security
When I select Account Settings or Security settings for the AT&T Yahoo email a login screen (username and password). After entering the username and password, the site throws me back to currently.att.com instead of allowing me into the Account Settings or Security. Tried it several times, same result. Using Windows 10 with Edge browser, both kept up to date.
Due to contractual agreements and the nature of your issue, you'll need to contact AT&T for a resolution. When contacting AT&T support, it is very important that you provide your full AT&T email address so that they are able to successfully locate your account in their system. Here's how to contact them: https://help.yahoo.com/kb/account/sln25426.html