Not my account signed in.

Sometimes when I go to the account tab on my phone, there is some other email address connected to my phone.
Could I please get some information on WHY this would be happening?

More info:
Connected with sign in via google. Works for about an hour then another account is provided as information.

It is kind of terrifying that this happens but I am not finding any type of response or information on this. I was recently signed out of my active session.
I have changed my google password and reattempted, but the situation still happens.

PLEASE RESPOND!