Mumtaz from Pakistan writes:
My Yahoo account and email is not being logged in since last 02 weeks.I have tried all the resolutions available by Yahoo website.What is the solution to retrieve the account?
You say you’ve tried all of the Yahoo! recovery resolutions available, but I am going to go over them for those who aren’t familiar with the process. If you forget your password, Yahoo! Password helper should be able to help you by using your alternate e-mail address or your cellphone number to let you answer a security question and reset the password.
This also where you can let Yahoo! know if you think your account may have been hijacked or compromised in some way.
You can also recover a deactivated account as long as the account was not deactivated due to a violation of terms of service or due to inactivity. Yahoo! offers video instructions here. 
If it’s possible that you’ve just forgotten your username or password, you can check your stored password in Windows Credential Manager to make sure you’re inputting the correct information. Learn about that here. 
If none of this helps, you maybe be out of luck.