[Lordzy]

It's because you added a '!' before 'IsPlayerLoggedIn' which means if player is not logged in.

pawn Код:

CMD:factions(playerid, params[])
{
        new string[128], faction;
        if(!IsPlayerLoggedIn(playerid)) return SendClientMessage(playerid, COLOR_GREY, "You need to login first before using any command.");
        format(string, sizeof(string), "Los Santos Police Department | Leader: %s | Members: %d",FacInfo[PlayerInfo[playerid][1]][pFacLeader]);
        SendClientMessage(playerid, COLOR_WHITE, string);
        format(string, sizeof(string), "San Andreas Government | Leader: %s | Members: %d", FacInfo[faction][FacLeader], FacInfo[faction][facMembers]);
        SendClientMessage(playerid, COLOR_WHITE, string);
        format(string, sizeof(string), "The Hitman Agency | Leader: %s | Members: %d", FacInfo[faction][FacLeader], FacInfo[faction][facMembers]);
        SendClientMessage(playerid, COLOR_WHITE, string);
        format(string, sizeof(string), "San Andreas News | Leader: %s | Members: %d", FacInfo[faction][FacLeader], FacInfo[faction][facMembers]);
        SendClientMessage(playerid, COLOR_WHITE, string);
        format(string, sizeof(string), "Los Santos Fire and Medic Department | Leader: %s | Members: %d", FacInfo[faction][FacLeader], FacInfo[faction][facMembers]);
        SendClientMessage(playerid, COLOR_WHITE, string);
        format(string, sizeof(string), "Federal Bureau of Investigation | Leader: %s | Members: %d", FacInfo[faction][FacLeader], FacInfo[faction][facMembers]);
        SendClientMessage(playerid, COLOR_WHITE, string);
        return 1;
}

And while creating a topic, please use a descriptive title.