I will try to help you.
You can get a new password, a Yahoo! ID reminder, or both. If you forgot your Yahoo! ID or password, go to the Sign-in Problems page.
If you forgot your Yahoo! ID, you need to provide three pieces of information so we can confirm your identity:
Be sure to provide the same information you gave the last time you registered for a new Yahoo! ID or password XXXXX the last time you updated your account.
If you forgot your password, you can create a new one. But first you’ll have to provide the following information so we can confirm your identity:
A Reset Your Password XXXXX will be sent to your alternate email address. Click the link and enter your new password XXXXX the Reset your password XXXXX
If you entered your secret question incorrectly or forgot what you originally entered, for security reasons, we cannot tell you what your Yahoo! ID is or let you create a new password.
I don't understand this answer because it it not telling me anything I have not already tried. Besides this is not a Mac problem but must be a Yahoo problem. Except I have not been successful in getting help from Yahoo as to how to get out of the loop I'm in.
Also, sending me an answer by email doesn't help when the problem is that I can't get into email. Can someone text me on my cell phone XXX-XXX-XXXX?
Sorry we don't have that option.
I will opt out so other experts also can help you.