Has Yahoo Answers changed?

No my account had not been inactive prior to my log in problem. I came on YA most days. It would most unusual if I didn't come on YA for 2 days. It is probably November when the problem started but I didn't pursue it then because I was busy with other things. So even now my account with the login problem has only been inactive on YA since November. Otherwise, it is still used at the very least once daily for my emails. Could it be because of Yahoo's partners have changed. About the same time this happened the format and layout of my email account changed. Prior to those changeds it was called BT Yahoo Internet but is now just BT Internet.

If you had not logged into your old account for more than a year, consider it deactivated by Yahoo/Verizon. Deactivating inactive accounts is not something new for Yahoo. The link below is to the help page for users having trouble signing into their account. 

Yahoo Answers has Changed a lot over the years 

Did you not Login into your Account for a period of time ? Yahoo Deletes inactive Accounts so if you dont Login After a Certain Period of time Yahoo will Delete your Account

If it has been more than one year you won't be able to get it back. It no longer exists. Yahoo accounts are deleted after 12 months of inactivity if they aren't used in that time.