Cms error : 530

I have been using quectel ec200u modem and getting an error CMS Error :530 when trying to send a test sms could anyone help me out?

void send_sms ( String sms)
{

const char phone = “+1***********7”;//this number is a original phone number in use

  //clearing data in soft serial
  S_flush = soft_Serial.readString();


  soft_Serial.println("AT+CSMP=17,167,0,0");// set SMS formatt as text
   delay(1000);
  soft_Serial.print("AT+CSCS=");// set SMS formatt as text

  soft_Serial.print("\"");

  soft_Serial.print("GSM");

  soft_Serial.println("\"");
   delay(1000);
  soft_Serial.println("AT+CNMI=2,1,0,0,0");// set SMS formatt as text
   delay(1000);
  soft_Serial.println("AT+CMGD=1,4");
   delay(1000);
  soft_Serial.println("AT"); //Sets the GSM Module in Text Mode

  //sending SMS using phone
  soft_Serial.print("AT+CMGF=1\r");  //Set text mode
  delay(3000);
  soft_Serial.print("AT+CMGS=\""+String(phone)+"\"\r"); //Send message
  delay(1000);
  soft_Serial.print(sms);//Text message
  delay(1000);
  soft_Serial.println((char)0x1A); //Ctrl+Z

  //printing the response in serial monitor when available
  while (soft_Serial.available() == 0);
  response = soft_Serial.readString();  // reading the response of the softwareserial (gsm module)
  Serial.println(response);

}

Hello, is it Python or C?

send_sms.c (5.9 KB)

usage: ./send_sms <> <> <>
eg: ./send_sms /dev/ttyUSB1 13712345678 message

its a arduino code. i have given the snippet where the sms is sent