How do I fix this Arduino issue? I can use this same code to send data to thingspeak it does not work with my created server

Question

String writeData="GET /setignition?id=64e807c734c47f4c9fc391e0&value=9";
Serial.println(writeData);
sendCommand("AT+CIPMUX=1",5,"OK");
sendCommand("AT+CIPSTART=0,\"TCP\",\""+ HOST + "\","+ PORT,15,"OK");
sendCommand("AT+CIPSEND=0," +String(writeData.length()+4),4,">");
Serial2.println(writeData);
Serial.println(writeData);

Answer 1

Can you clarify the exact type of arduino, and the exact error you see?