HTTPS POST method fails in esp32

Question

I was trying to connect with server but, I was unable to post the data. I have added the SSL key to connect with server that is happening but HTTPS POST is not. I tried the same method with http, I am able to connect with server in that case.

/* set SSL/TLS certificate */
    client.setCACert(ca_cert);
//////////////////////////////// try to connect to server again and POST the data on the cloud //////////////////////////
  if (!client.connect(host, httpsPort)) {
     Serial.println("Connection failed!");
  } else {
     Serial.println("Connected to server!"); 
     client.println("POST /devices/deviceData HTTP/1.1");
     client.println("Host: api.thi***i.io");
     client.println("cache-control: no-cache");
     client.println("Content-Type: application/json");
     client.println("Authorization: Bearer eyJ0e***");
     client.println("Postman-Token: b1f4e147-8d13-4a27-a1a9-b****");
     client.print("Content-Length: ");
     client.println(PostValue.length());
     client.println();
     client.println(PostValue);
  }
  Serial.print("Waiting for response ");
  while (client.available() == 0) {
     if (millis() - timeout > 50000) {
        Serial.println(">>> Client Timeout !");
        client.stop();
        return;
     }
  }

  Serial.println("Response From Server");
  while(client.available()) { 
     char c = client.read();
     Serial.write(c);       
  }

It should connect from my logic but I am getting server error 400. Can I know, what can be issue here?