[Jstylezzz]

Since you didn't show any code, I'm not sure how you did everything.
If you do something like the samp wiki said:

pawn Код:

new gangzone;
 
public OnGameModeInit()
{
    gangzone = GangZoneCreate(1248.011, 2072.804, 1439.348, 2204.319);
    return 1;
}
 
public OnPlayerSpawn(playerid)
{
    GangZoneFlashForPlayer(playerid,gangzone,COLOR_RED);
    return 1;
}

It might work.
Check: https://sampwiki.blast.hk/wiki/GangZoneFlashForPlayer

If this doesn't work, show some code, so we'll be able to help