Factory reset sim800l

What is the AT command to return the module to its factory configuration. I wrote the RDY command and I don’t know how to remove it.

I guess you can just reset the saved configurations, It might be AT&F command

I already run that command and then the AT&W command to save.
Add the capacitor to the power supply to rule out source problems.
Perform the following code, and I see that the radio signal (AT + CSQ) is intermittent.
I did the same test with another module and it always reports between 7 and 15 in response to the AT + CSQ command.
I think the module has problems.

CODE::::::::

#include <SoftwareSerial.h>

//Create software serial object to communicate with SIM800L
SoftwareSerial mySerial(2, 3); //SIM800L Tx & Rx is connected to Arduino #8 & #7

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

//Begin serial communication with Arduino and SIM800L
mySerial.begin(9600);

Serial.println(“Initializing…”);
delay(1000);

mySerial.println(“ATE1”); //Once the handshake test is successful, it will back to OK
updateSerial();
mySerial.println(“AT”); //Once the handshake test is successful, it will back to OK
updateSerial();
mySerial.println(“AT+CSQ”); //Signal quality test, value range is 0-31 , 31 is the best
updateSerial();
mySerial.println(“AT+CPIN?”); //Insert SIM test,
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();
mySerial.println(“AT+CGSN”); //Check whether it has registered in the network
updateSerial();

Serial.println(“Fin…”);
}

void loop()
{
delay(2000);
mySerial.println(“AT+CSQ”);
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 Por6+t
}
}