SIM900 TCP connection issue

Projects Programming
2

I have been informed that I should switch to different commands, which I have. My code now looks like:

void SubmitHttpRequest()
{
  Serial1.println("AT+CSQ");
  delay(100); 
  ShowSerialData();// this code is to show the data from gprs shield, in order to easily see the process of how the gprs shield submit a http request, and the following is for this purpose too.
 
  Serial1.println("AT+CGATT?");
  delay(100); 
  ShowSerialData();
 
  Serial1.println("AT+SAPBR=3,1,\"CONTYPE\",\"GPRS\"");//setting the SAPBR, the connection type is using gprs
  delay(1000); 
  ShowSerialData();
 
  Serial1.println("AT+SAPBR=3,1,\"APN\",\"everywhere\"");//setting the APN, the second need you fill in your local apn server
  delay(4000); 
  ShowSerialData();

 //Enable GPRS
  Serial1.println("AT+SAPBR=1,1");
  delay(2000); 
  ShowSerialData();

  //Query if connection is setup correctly, return IP address if it is 
  Serial1.println("AT+SAPBR=2,1");
  delay(2000); 
  ShowSerialData();

  Serial1.println("AT+HTTPSSL=1"); //enable HTTPS
  delay(2000); 
  ShowSerialData();
 
  Serial1.println("AT+HTTPINIT"); //init the HTTP request 
  delay(2000); 
  ShowSerialData();

  Serial1.println("AT+HTTPPARA=\"CID\",1");//setting the SAPBR, for detail you can refer to the AT command mamual
  delay(2000); 
  ShowSerialData();
  
  Serial1.println("AT+HTTPPARA=\"URL\",\"https://rocky-garden-56471.herokuapp.com/breadcrum/lifecycle/register\"");
  delay(6000); 
  ShowSerialData();

  Serial1.println("AT+HTTPPARA=\"CONTENT\",\"application/json\"");
  delay(3000); 
  ShowSerialData();  

  Serial1.println("AT+HTTPDATA=200,10000");// setting the httppara, the second parameter is the website you want to access
  delay(3000);
  ShowSerialData();
 
  Serial1.println("{\"device_info\":\"breadcrum-prototype-a\"}");// setting the httppara, the second parameter is the website you want to access
  delay(3000); 
  ShowSerialData();
 
  Serial1.println("AT+HTTPACTION=1");//submit the request //0:READ 1:POST 2:HEAD
  delay(10000);//the delay is very important, the delay time is base on the return from the website, if the return datas are very large, the time required longer.
  ShowSerialData();
 
  Serial1.println("AT+HTTPREAD");
  delay(1000); 
  ShowSerialData();

  Serial1.println("AT+HTTPTERM");
  delay(1000); 
  ShowSerialData();
 
  Serial1.println("");
  delay(100);
}

This gives me the result of:

AT+CSQ

+CSQ: 18,0

OK
AT+CGATT?

+CGATT: 1

OK
AT+SAPBR=3,1,"CONTYPE","GPRS"

OK
AT+SAPBR=3,1,"APN","everywhere"

OK
AT+SAPBR=1,1

ERROR
AT+SAPBR=2,1

+SAPBR: 1,1,"31.94.203.234"

OK
AT+HTTPSSL=1

OK
AT+HTTPINIT

OK
AT+HTTPPARA="CID",1

OK
AT+HTTPPARA="URL","https://rocky-garden-56471.herokuapp.com/breAT+HTTPPARA="CONTENT","application/json"

OK
AT+HTTPDATA=100,10000

DOWNLOAD

ERROR
AT+HTTPREAD

OK
AT+HTTPTERM

OK

Which is incredibly close, as (ignore the connection error which has appeared because I was already connected) I only have the single error on download. I can't seem to figure out why this is happening, changing delays and data size doesn't appear to make any difference. Any idea what could be causing this?