Comunication with module sim800l

Hello everyone, I am trying to use the arduino module sim800l but when i try to send some at command, like a siple AT, I get in response '???' in loop and I do understand the cause of this.
Another problem is the alimentation of this module that requires 2-3 A when it send messages, for now i would be happy if i can establish a undersandable comunication with it so I didn't put the sim in the slot.
Here is the code that I am using:


#include <SoftwareSerial.h>

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

void setup()  
{
  // Open serial communication
  Serial.begin(9600);

  // set the data rate for the SoftwareSerial port
  mySerial.begin(9600);
  
  Serial.println("Testing SIM800L module");

  delay(1000);

}

void loop() // run over and over
{
  updateSerial();  
}


void updateSerial(){
  delay(500);  
  while( mySerial.available() )
  {
    mySerial.write(Serial.read());
  }
 
  while(Serial.available())
  { 
    Serial.write(mySerial.read());
  }
}

and here are some photos of the connections:



and here is the link of the battery that i am using:

Please follow the advice given in the link below when posting code. Use code tags (the </> icon above the compose window) to make it easier to read and copy for examination

sorry i didnt see the button

Your post was MOVED to its current location as it is more suitable.

Ooops times two..

while( mySerial.available() ) //Should be Serial.available() ?
  {
    mySerial.write(Serial.read());
  }
 
  while(Serial.available()) //Should be mySerial.available() ?
  { 
    Serial.write(mySerial.read());
  }

yes thanks a lot you are right, i dont understand how could I miss it, thanks again

do you know how could i resolve the alimentation problem? i bought this battesies becouse i watched a video on youtube but it doesnt seem working

What exactly is the matter with your current battery configuration? Does it work alright with a power supply?

The led of the module should blink every 3 seconds when it is connected to the sim network but it blinks every seconds and this means that it is trying to connect but it cannot so it restart the attempt of connecting.
I opened a new argoment at this link for this problem : sim800L problems to connecting to the sim network (blinking problem)