Please note: if you do not sign in to your Yahoo Mail account for 12 consecutive months or longer, your account will be deleted due to inactivity.
To sign in to Yahoo:
Go to the Yahoo log in page: https://login.yahoo.com Enter your Yahoo ID (email address) and password
Help for Yahoo Account https://help.yahoo.com/kb/account
This is how to recover your account if you have password/sign in problems: https://help.yahoo.com/kb/SLN2824.html