I received yesterday my brand new Arduino MKR GSM 1400 and started playing around with today.

However, I'm having trouble stablishing the connection with the SIM card. I'm using the "ReceiveSMS" example from the MKRGSM library (code below), but the execution is getting stuck at the gsmAccess.begin(PINNUMBER) command.

Using AT commands and the debug mode, I got the following description for the error message:

AT+CPIN?
+CME ERROR: SIM not inserted

I have tried connecting with 3 different SIM cards, all tested beforehand with a smartphone and confirmed to be functional. I have tried removing the PIN, but still got the same error.

Does anybody have any idea on what could be going wrong?

Thanks in advance

Code:

// include the GSM library
#include <MKRGSM.h>

#include "arduino_secrets.h" 
// Please enter your sensitive data in the Secret tab or arduino_secrets.h
// PIN Number
const char PINNUMBER[] = SECRET_PINNUMBER;

// initialize the library instances
GSM gsmAccess;
GSM_SMS sms;

// Array to hold the number a SMS is retreived from
char senderNumber[20];

void setup() {
  // initialize serial communications and wait for port to open:
  Serial.begin(9600);
  while (!Serial) {
    ; // wait for serial port to connect. Needed for native USB port only
  }

  Serial.println("SMS Messages Receiver");

  // connection state
  bool connected = false;

  // Start GSM connection
  while (!connected) {
    if (gsmAccess.begin(PINNUMBER) == GSM_READY) {
      connected = true;
    } else {
      Serial.println("Not connected");
      delay(1000);
    }
  }

  Serial.println("GSM initialized");
  Serial.println("Waiting for messages");
}