[Threshold]

What I would suggest would be to use Incognito's streamer, believe it or not. First of all, create a dynamic area using CreateDynamicRectangle, then use OnPlayerLeaveDynamicArea. Meaning, that when a player exits the cell area, and they are NOT jailed, then you can kick/ban the player.

pawn Код:

public OnPlayerLeaveDynamicArea(playerid, areaid)
{
    if(areaid == mycellarea) //mycellarea is not defined, and must be defined using CreateDynamicRectangle
    {
        if(IsPlayerInJail[playerid]) //Also not defined, replace this with your variable that defines whether a player is jailed or not
        {
            Kick(playerid); //Or Ban(playerid); etc.
        }
    }
    return 1;
}

This is just an example and won't function properly if you paste it into your script.