Who changed the password of your SQL Login? It is a real world question every DBA faces one day. Bookmark this post, here is how to find the answer.
Contained Database Users: Logins That Move With the Database
Use contained database users to move authentication with a database, inspect prerequisites, test connections, and review access ownership.
Renaming or Disabling the sa Login
Renaming or disabling the sa login requires a dependency inventory, tested alternate admin access, and monitoring after the change.