If you've got 4 accounts on there, one of them is going to be the one you want.
Find out which one it is (maximum 4 "restarts" needed), and set that as the default with control userpasswords2. Check it works, leave it for a couple of days to be sure. Then delete the other accounts to prevent confusion.
You might, depending on your attitude to security, want to have a "default start" account which is you, but not an admin. A separate, no details one for adminny things.