i tried to log onto my email (yahoo) with an email address that is 20 plus years old, broke today

I tried to log onto our yahoo browser today to check email and it does not work anymore.  I have run McAfee tools to check for issues and don't seem to find anything.  has something happened with yahoo since yesterday.  when I try to log into yahoo or yahoo email it accepts the userid but not the password.  it sends me to an AT&T screen to try to recover or reset the password but then says it cannot find a secured way to recover the password.  what's going on???    I would like for you to be able to send your answer to my email [Edited for privacy-This is a public forum. Please do not post personal or unique information such as but not limited to full names, employee ID numbers, email addresses, phone numbers, account numbers, etc]

Jim