I got logged out and i cant log back in

I opened tiktok and it said my account got logged out, my log in is through facebook, i tried to log in but it told me to put my birthday and create a new name, i found it weird and closed, when i was back i was suddenly on a new account, i tried to log back in my daily account but i get dragged to the new account, idk what to do, i tried to delete the new account but it keeps showing up when i try to log in to my daily account