Can't Sign In with Game Center?

Please try an uninstall and reinstall of Jeopardy! World Tour+, and while the game is uninstalled, ensure you're logged into your Game Center account on your device.

When you reinstall, connect to a steady internet source and you should then be able to secure your account with Game Center to begin playing!

If you're still facing issues trying to Sign In, access your Settings App and select Game Center. Select the Sign Out button on the bottom. Once you're Signed Out, Sign back in to Game Center and relaunch the game.

Tip:
Securing your account over a steady wifi connection will greatly reduce the chances of running into a Connection Error!