Sim800l SMS können nicht Empfangen werden

#include <GSMSim.h>

#define RX 7

#define TX 8

#define BAUD 9600

GSMSim gsm;

/*

 * Also you can this types:

 * GSMSim gsm(RX, TX);

 * GSMSim gsm(RX, TX, RESET);

 * GSMSim gsm(RX, TX, RESET, LED_PIN, LED_FLAG);

 */

void setup() {

pinMode(10,OUTPUT);

digitalWrite(10,HIGH);

  // put your setup code here, to run once:

  Serial.begin(9600);

 // Serial.println("GSMSim Library - SMS Example");

 // Serial.println("");

 // delay(1000);

  gsm.start(); // baud default 9600

  //gsm.start(BAUD);

 // Serial.println("Changing to text mode.");

  gsm.smsTextMode(true); // TEXT or PDU mode. TEXT is readable :)

  //char* number = "+4916090682193";

 // char* message = "Hi my friend. How are you?"; // message lenght must be <= 160. Only english characters.

//Serial.println("SMS Löschen");

//Serial.println(gsm.smsDeleteAll());

  //Serial.println("Sending Message --->");

  //Serial.println(gsm.smsSend(number, message)); // if success it returns true (1) else false (0)

 // delay(2000);

  Serial.println("Listing unread message(s).");

  Serial.println(gsm.smsListUnread()); // if not unread messages have it returns "NO_SMS"

  Serial.println("Read SMS on index no = 1");

  Serial.println(gsm.smsRead(1)); // if no message in that index, it returns IXDEX_NO_ERROR

}

void loop() {

  // put your main code here, to run repeatedly:

}