[DandoRYx]

Maybe try this, I added killerid != playerid

pawn Code:

public OnPlayerDeath(playerid, killerid, reason)
{
    if(killerid != INVALID_PLAYER_ID && killerid != playerid)
    {
        SetPlayerScore(killerid, GetPlayerScore(killerid) + 1);
        SendDeathMessage(killerid,playerid,reason);
        GivePlayerMoney(killerid, 2500);
    }
    else
    {
        SendDeathMessage(INVALID_PLAYER_ID,playerid,reason);
    }
    GivePlayerMoney(playerid, -1000);
    return 1;
}