Play into the tutorial enough to get the connect button to appear in the settings menu. It's not there initially, but you don't have to play into the tutorial part for very long. Once it does, connect it back to your actual account and you should be good to go.
On rare occasion mine will still send me back to the generic unlinked tutorial account if I'm swapping from my main to alt accounts, or vice versa. When that happens, I just force close the game and manually restart it. Then when it hits the splash screen, the sign in option appears