[JaTochNietDan]

Because you have this in a loop.

pawn Код:

format(string, 128, "Type /signcheck %d to receive your paycheck.", CheckNumber[i]);
SendClientMessageToAll(COLOR_LIGHTBLUE, string);

The loop is running 499 times and the message will be sent to everyone everytime a player is online according to your code. What you need to quite simply do, is change

SendClientMessageToAll

to

SendClientMessageToPlayer(i,COLOR_LIGHTBLUE,string );