SIM900 shield with UNO communication error

Dear Forumers!

I just bought a new Arduino UNO controller and a new SIM 900 GSM shield.
My problem is, I can’t communicate with the SIM 900 via the UNO controller.

I followed this tutorial for wiring. i’m using the Software Serial jumpers and common grounds includes the TX-RX pins as I can read in the tutorial.
The shield successfully connected to the network (The Netlight LED flasing every 3 seconds).

I tried with an USB to TTL converter but nothing response from SIM900. The commands that I use are AT commands like “AT” which will responses “OK” but nothing happens. I’ve tried lots of baud rates and “Both NL & CR” option selected on the IDE Terminal.

I tried this tutorial but the results is the same as I told :/. No response from the shield.

The shield is dead or I need a firmware upgrade?

Any ideas?

Thanks in advance!

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Sorry, this is my shield: SIM900

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I don't asked for support from this store, I just buy it. It's not an original arduino product? Which is original? The UNO board is an original Arduino board from this store.

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Boards and output:

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My code:

#include <SoftwareSerial.h>

//Create software serial object to communicate with SIM900
SoftwareSerial mySerial(7, 8); //SIM900 Tx & Rx is connected to Arduino #7 & #8

void setup()
{
  //Begin serial communication with Arduino and Arduino IDE (Serial Monitor)
  Serial.begin(9600);
  
  //Begin serial communication with Arduino and SIM900
  mySerial.begin(9600);

  Serial.println("Initializing...");
  delay(1000);

  mySerial.println("AT"); //Handshaking with SIM900
  updateSerial();
  mySerial.println("AT+CSQ"); //Signal quality test, value range is 0-31 , 31 is the best
  updateSerial();
  mySerial.println("AT+CCID"); //Read SIM information to confirm whether the SIM is plugged
  updateSerial();
  mySerial.println("AT+CREG?"); //Check whether it has registered in the network
  updateSerial();
}

void loop()
{
  updateSerial();
}

void updateSerial()
{
  delay(500);
  while (Serial.available()) 
  {
    mySerial.write(Serial.read());//Forward what Serial received to Software Serial Port
  }
  while(mySerial.available()) 
  {
    Serial.write(mySerial.read());//Forward what Software Serial received to Serial Port
  }
}

My board & wiring link for image):

Serial monitor output (Serial output and picture for link):

Initializing...

image link: Pasteboard - Uploaded Image

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As I can see in this picture for using software serial I need to use the D7 and the D8 jumpers. But i tired with D0 and D1 and nothing happens.

If I place the shield to the top of the Arduino UNO I need to switch the EXTN PWR switch to off on the GSM shield right?