How can I be sure whoever hacked my account they still not have access?

Answer 1

Apparently somebody has gotten access to the Yahoo database because two people that I had no idea who they are started using my account using my telephone number and attempting to copy the information that I had placed on Yahoo's account.

I purposely placed some information so I would know the origin. Anyway I deleted the two users that got into my account change the password and opened a new account. Within 10 minutes the same people were trying to get in to my new account.

Answer 2

This is how to recognize and secure a hacked account: https://help.yahoo.com/kb/SLN3516.html

Answer 3

https://help.yahoo.com/kb/SLN2073.html?guccounter=...