SIM800L not responding to AT commands

Question

I am using SIM800L module the module. I am new to GSM modules, so I've searched for the basic to use the GSM with the Arduino. this is my code.

#include <SoftwareSerial.h>

SoftwareSerial mySerial(2, 3); // RX, TX

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  mySerial.begin(9600);
}

void loop() {
  if (mySerial.available()) {
    Serial.write(mySerial.read());
  }

  if (Serial.available()) {
    mySerial.write(Serial.read());
  }
}

when I send any AT commands to the GSM I didn't find any respond, so I changed the baud rate of mySrial and try different rates to get any respond, but I didn't get anything.

The wiring of the circuit is:

• The 5V of the GSM connected to 5V of a power supply (the maximum current of it is 3A).
• The GND of the GSM to the GND of the power supply.
• TX of the GSM to pin 2 of the Arduino.
• RX of the GSM to pin 3 of the Arduino.
• GND to to GND of the Arduino.

The module has two LEDs:

• the first one D6 NET blanking every second.
• the second one D2 RING blanking every (7, 6, 8 or 9) times of the first one.