In Great Little War GameEdit
In Great Little War Game, this bug is caused by the next turn button coming up at all times when the mission intro ends. You must be in a menu when it comes up to trigger the bug. This means you must fail a mission, because the menu button only appears during mission introductions when you press the retry button in the failed mission menu.
In Great Big War GameEdit
In Great Big War Game, the bug can occur anywhere in gameplay. It is caused by tapping the "Next Turn" button when the Pause menu is opening.