dcmd_kickall(playerid,params[]) {
#pragma unused params
	if(PlayerData[playerid][Level] == 4 || IsPlayerAdmin(playerid))
	{
	for(new i=0; i<MAX_PLAYERS; i++)
	{
	new ownername[MAX_PLAYER_NAME],string[76];
	GetPlayerName(playerid,ownername,sizeof(ownername));
	format(string,sizeof(string),"[ SERVER ] You all have been kicked by server owner %s !",ownername);
	SendClientMessageToAll(COLOUR_CRIMSON,string);
	Kick(i);
	}
  }
	return 1;
}

if(i != playerid)
{
// continue with your code.
}