hopeless, beyond help. usually referring to a situation/someone having gone out of control.

Got the covid-19 vaccine

Originally came from a game called "29" played in India. Game consists of 4 players, 2 teams of 2, and the goal was to get 29 points in one game. If you or your partner would lose the game, you would say that you're "gone case" meaning you lost the hand or the game. Definition now extends to many meanings of the word gone, gone can mean, asleep, drunk, dead, not here, etc