I created three email ids. But only two can be seen now. So when i tried to create again, it says "User already exists."

I check if it is the secondary email of admin. Also, I tried to Login to this account to delete it, but it says Password is wrong.

Looks like many have asked the same question. If this is this much confusing, I wonder why guys haven't taken the effort to simply this area.

I have checked all options, please help. 

Thanks