NodeMcu Serial Comm IOT

// BLYNK INTERFACE CONNECTIVITY
#define BLYNK_TEMPLATE_ID "TMPLmihvENoF"
#define BLYNK_DEVICE_NAME "Weight Sensor"
#define BLYNK_AUTH_TOKEN "v_f8skPGopj52y7vwTu5aeMBl4wiCkBa"
#define BLYNK_PRINT Serial

#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>
#include <SoftwareSerial.h>
SoftwareSerial NodeMcu(D2,D3); 


// Your WiFi credentials.
// Set password to "" for open networks.
char ssid[] = "Virus1";
char pass[] = "Pandemic_2019";
char auth[] = "v_f8skPGopj52y7vwTu5aeMBl4wiCkBa";

BlynkTimer timer;

String myString;          // complete message from arduino, which consistors of sensors data
char rdata;               // received characters

int firstVal, secondVal;  // sensor values 
// This function sends Arduino's up time every second to Virtual Pin (1).
// In the app, Widget's reading frequency should be set to PUSH. This means
// that you define how often to send data to Blynk App.

void myTimerEvent()
{
  // You can send any value at any time.
  // Please don't send more that 10 values per second.
  Blynk.virtualWrite(V1, millis() / 1000);
}


void setup()
{

  Serial.begin(115200);
  NodeMcu.begin(9600);
  Blynk.begin(auth, ssid, pass);

  timer.setInterval(1000L,Voltage_sensorvalue); 
  timer.setInterval(1000L,Weight_sensorvalue); 

}

void loop()
{
   if (NodeMcu.available() == 0 ) 
   {
  Blynk.run();
  timer.run(); // Initiates BlynkTimer
   }
   
  if (NodeMcu.available() > 0 ) 
  {
    Serial.println(rdata);
    rdata = Serial.read(); 
    myString = myString+ rdata; 
  
    if( rdata == '\n')
    {
     Serial.println(myString); 
  
String l = getValue(myString, ',', 0);
String m = getValue(myString, ',', 1);



firstVal = l.toInt();
secondVal = m.toInt();
  
  myString = "";
  
    }
  }

}

void Voltage_sensorvalue()
{
int sdata = firstVal;
  // You can send any value at any time.
  // Please don't send more that 10 values per second.
  Blynk.virtualWrite(V2, sdata);

}
void Weight_sensorvalue()
{
int sdata = secondVal;
  // You can send any value at any time.
  // Please don't send more that 10 values per second.
  Blynk.virtualWrite(V3, sdata);

}

String getValue(String data, char separator, int index)
{
    int found = 0;
    int strIndex[] = { 0, -1 };
    int maxIndex = data.length() - 1;

    for (int i = 0; i <= maxIndex && found <= index; i++) {
        if (data.charAt(i) == separator || i == maxIndex) {
            found++;
            strIndex[0] = strIndex[1] + 1;
            strIndex[1] = (i == maxIndex) ? i+1 : i;
        }
    }
    return found > index ? data.substring(strIndex[0], strIndex[1]) : "";
}