PLEASE HELP SMS PHONE NUMBER COMPARE

HELLO, I NEED HELP PLEASE
I WANT TO COMPARE THE PHONE NUMBER THAT SENDS AN SMS TO A VARIABLE BUT I DONT HAVE THE RESULT I WANT -Serial.println("correct sender");-
HERE IS MY CODE

// include the GSM library
#include <GSM.h>
// PIN Number for the SIM
#define PINNUMBER ""
// initialize the library instances
GSM gsmAccess;
GSM_SMS sms;
// Array to hold the number a SMS is retreived from
char senderNumber[20];
int myphone = +306971234567;

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
  boolean notConnected = true;
  // Start GSM connection
  while (notConnected) {
    if (gsmAccess.begin(PINNUMBER) == GSM_READY) {
      notConnected = false;
    } else {
      Serial.println("Not connected");
      delay(1000);
    }
  }
  Serial.println("GSM initialized");
  Serial.println("Waiting for messages");
}

void loop() {
  char c;
  // If there are any SMSs available()
  if (sms.available()) {
    if (myphone == senderNumber[20]) {
      Serial.println("correct sender");
    }
    Serial.println("Message received from:");
    // Get remote number
    sms.remoteNumber(senderNumber, 20);
    Serial.println(senderNumber);
  }
  sms.flush();
  delay(1000);
}

HELLO, I NEED HELP PLEASE

A hearing aid, perhaps. Stop screaming.

int myphone = +306971234567;

Bullshit.

    if (myphone == senderNumber[20]) {

The index value 20 is beyond the end of the array. The memory at that location is owned by some other variable or array or code, and is extremely unlikely to equal the nonsense you have tried to store in that int.

Store the phone number you want to compare to in a string. Store the phone number you have properly extracted from the SMS in another string. Compare the two strings using strcmp().

Done thanks PaulS

void loop() {
  char c;
   phone1 = String ("+123456789");
  // If there are any SMSs available()
  if (sms.available()) {
    Serial.println("Message received from:");
    // Get remote number
    sms.remoteNumber(senderNumber, 20);
    Serial.println(senderNumber);
    if (phone1 == senderNumber) {
      Serial.println("correct sender");
    }  
  }
  sms.flush();
  delay(1000);
}

I am new in Arduino and Forum PaulS, i will learn. ;D