[The__]

Okay, this is what I've done in the past.

some where:

pawn Код:

new TruckLoadX[MAX_PLAYERS];
new TruckLoadY[MAX_PLAYERS];
new TruckLoadZ[MAX_PLAYERS];

onplayer connect reset them:

pawn Код:

TruckLoadX[playerid] = 0;
TruckLoadY[playerid] = 0;
TruckLoadZ[playerid] = 0;

pawn Код:

public LoadMats(playerid)
{
    new rand = random(sizeof(TruckingUnload));
    TruckLoadX[playerid] = TruckingUnload[rand][0];
    TruckLoadY[playerid] = TruckingUnload[rand][1];
    TruckLoadZ[playerid] = TruckingUnload[rand][2];
    SetPlayerCheckpoint(playerid, TruckLoadX[playerid],TruckLoadY[playerid],TruckLoadX[playerid], 7.0);
    SendClientMessage(playerid, COLOR_ORANGE, "INFO: {FFFFFF}Pergilah ke checkpoint yang berada di map");
    TogglePlayerControllable(playerid, 0);
    return 1;
}

Your checkpoint for unloading change too:

pawn Код:

if(IsPlayerInRangeOfPoint(playerid, 7.0, TruckLoadX[playerid],TruckLoadY[playerid],TruckLoadZ[playerid]))
{
    if(work[playerid] == 1)
    {
        GivePlayerMoney(playerid, 4000);
        SendClientMessage(playerid, COLOR_ORANGE, "INFO: {FFFFFF}you have passed trucking job and get reward $4.000");
        DisablePlayerCheckpoint(playerid);
        Work[playerid] = 0;
        return 1;
    }
}

Might work, could try it, dunno.