Unable to log in using email. Can only log in using our member name

For the past week, have not been able to log into Ebay using email address, Can only log in using our member name. 

Is this something that has been changed, or a Technical issue?  Used to having two options for sign in.  (User name or Email) When trying to log in using email, a message appears saying the 

password doesn't match.  When logging in with our member name, not a problem.