[Jason`]

Try:

pawn Код:

CMD:duty(playerid) {
    if(isnull(params))
        return SendClientMessage(playerid, -1, "Type /duty [on/off]");
        
    static
        playerName[MAX_PLAYER_NAME];

    if(!strcmp(params, "on", true)) {
        GetPlayerName(playerid, playerName, sizeof playerName);
        SetPVarString(playerid, "name", playerName);
        SetPlayerName(playerid, "WOLF");
        return 1;
    }
    if(!strcmp(params, "off", true)) {
        if(GetPVarType(playerid, "name")) {
            GetPVarString(playerid, "name", playerName, sizeof playerName);
            SetPlayerName(playerid, playerName);
            return 1;
        }
    }
    return 1;
}