[Konstantinos]

You declare "idx" so it's by default 0. Then you check if the player is in range of the first garage (that you probably are not). Loop through garages and check if the player is in range of any of those garages and do your code.

And by the way checking if the player is inside the current vehicle he is, it's a bit pointless. Just use the check about the state (if it's PLAYER_STATE_DRIVER).