Data is not being to google sheets from ESP8266

The main objective of this program is to send the value of the variable called 'Count' from ESP8266 to google sheets. When I tried to test this, I was only able to get the value of Count from the OLED Display and neither it was displayed on the serial monitor nor it was sent to the google sheets. I have checked my code multiple times and I think There isn't any sort of syntax error. I would kindly request you to point out any logical or any other programming errors that I have made, so that I can learn from my mistakes. NOTE : I have used an Arduino mega 2560 with built in wifi module wherein I have configured the board to only act as an ESP8266.

#include <ESP8266WiFi.h>
#include "HTTPSRedirect.h"
#include <SPI.h>
#include <MFRC522.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

const char* ssid = "Galaxy M3xxxx";
const char* password = "nxen015xxxxx";
// pins assignment
constexpr uint8_t RST_PIN = 8;     // Configurable, see typical pin layout above
constexpr uint8_t SS_PIN = 9;     // Configurable, see typical pin layout above
#define screen_width 128
#define screen_height 64

Adafruit_SSD1306 display(-1);
MFRC522 mfrc522(SS_PIN, RST_PIN);   // Create MFRC522 instance.
int j=0;

const char* GScriptId = "AKfycbw1JtQ4bKM3UgnwLamcFwrKqFgnnw1CLsRO2c7lsQDFMhHgqd2iHCA8qEUGA5ebynoWIA";
const int dataPostDelay = 3000;    // 3 seconds
const char* host = "script.google.com";
const char* googleRedirHost = "script.googleusercontent.com";
const int httpsPort =     443;

HTTPSRedirect client(httpsPort);

// Prepare the url (without the varying data)
String url = String("/macros/s/") + GScriptId + "/exec?";

const char* fingerprint = "F0 5C 74 77 3F 6B 25 D7 3B 66 4D 43 2F 7E BC 5B E9 28 86 AD";

void setup() {
    Serial.begin(115200);
    Serial.println("Connecting to wifi: ");
    Serial.println(ssid);
    Serial.flush();

  SPI.begin();      // Initiate  SPI bus
  mfrc522.PCD_Init();   // Initiate MFRC522
  Serial.println("Approximate your card to the reader...");
  Serial.println();

  display.begin(SSD1306_SWITCHCAPVCC,0x3C);
  display.clearDisplay();
  display.setTextSize(2);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,0);
  display.print("Count");
  display.display();

    WiFi.begin(ssid, password);
    while (WiFi.status() != WL_CONNECTED) {
            delay(500);
            Serial.print(".");
    }
    Serial.println(" IP address: ");
    Serial.println(WiFi.localIP());

    
    Serial.print(String("Connecting to "));
    Serial.println(host);
    bool flag = false;
    for (int i=0; i<5; i++){
            int retval = client.connect(host, httpsPort);
            if (retval == 1) {
                        flag = true;
                        break;
            }
            else
                    Serial.println("Connection failed. Retrying…");
    }

    // Connection Status, 1 = Connected, 0 is not.
    Serial.println("Connection Status: " + String(client.connected()));
    //Serial.flush();
    
    if (!flag){
            Serial.print("Could not connect to server: ");
            Serial.println(host);
            Serial.println("Exiting…");
            Serial.flush();
            return;
    }

    // Data will still be pushed even certification don’t match.
   /* if (client.verify(fingerprint, host)) {
            Serial.println("Certificate match.");
    } else {
            Serial.println("Certificate mis-match");
    }*/
    

}


// This is the main method where data gets pushed to the Google sheet
void postData(String tag, float value){
    if (!client.connected()){
            Serial.println("Connecting to client again…");
            client.connect(host, httpsPort);
    }
    String urlFinal = url + "tag=" + tag + "&value=" + String(value);
    client.printRedir(urlFinal, host, googleRedirHost);
}


// Continue pushing data at a given interval
void loop() {
     // Look for new cards
  if ( ! mfrc522.PICC_IsNewCardPresent()) 
  {
    return;
  }
  // Select one of the cards
  if ( ! mfrc522.PICC_ReadCardSerial()) 
  {
    return;
  }
  //Show UID on serial monitor
  Serial.print("UID tag :");
  String content= "";
  byte letter;
  for (byte i = 0; i < mfrc522.uid.size; i++) 
  {
     Serial.print(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " ");
     Serial.print(mfrc522.uid.uidByte[i], HEX);
     content.concat(String(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " "));
     content.concat(String(mfrc522.uid.uidByte[i], HEX));
  }
  Serial.println();
  Serial.print("Message : ");
  content.toUpperCase();
  if (content.substring(1) == "01 07 16 DB") //change here the UID of the card/cards that you want to give access
  {
    Serial.println("accepted");
    Serial.println();
    j++;
    Serial.println(j);
    tcount();
    display.display();   
    delay(dataPostDelay);
    
  }
 
 else   {
    Serial.println(" Access denied");
    delay(30);
  }


  
}


void tcount(void)
{
  display.clearDisplay();
  display.setTextSize(2);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0,0);
  display.print("Count");
  display.setCursor(40,40);
  display.print(j);
  display.display();

  
    int data = j;
    postData("Count",data); 
    Serial.println("Data has been posted !");

  
}   

The following code from the google sheets app script.

function doGet(e){
  Logger.log("--- doGet ---");
 
 var tag = "",
     value = "";
 
  try {
 
    // this helps during debuggin
    if (e == null){e={}; e.parameters = {tag:"test",value:"-1"};}
 
    tag = e.parameters.tag;
    value = e.parameters.value;
 
    // save the data to spreadsheet
    save_data(tag, value);
 
 
    return ContentService.createTextOutput("Wrote:\n  tag: " + tag + "\n  value: " + value);
 
  } catch(error) { 
    Logger.log(error);    
    return ContentService.createTextOutput("oops...." + error.message 
                                            + "\n" + new Date() 
                                            + "\ntag: " + tag +
                                            + "\nvalue: " + value);
  }  
}
 
// Method to save given data to a sheet
function save_data(tag, value){
  Logger.log("--- save_data ---"); 
 
 
  try {
    var dateTime = new Date();
 
    // Paste the URL of the Google Sheets starting from https thru /edit
    // For e.g.: https://docs.google.com/..../edit 
    var ss = SpreadsheetApp.openByUrl("https://docs.google.com/spreadsheets/d/1HDVGsOEqkz_4mSeTHYLJxWL99EomohwIcOP8CEdfO7g/edit");
    var summarySheet = ss.getSheetByName("Summary");
    var dataLoggerSheet = ss.getSheetByName("DataLogger");
 
 
    // Get last edited row from DataLogger sheet
    var row = dataLoggerSheet.getLastRow() + 1;
 
 
    // Start Populating the data
    dataLoggerSheet.getRange("A" + row).setValue(row -1); // ID
    dataLoggerSheet.getRange("B" + row).setValue(dateTime); // dateTime
    dataLoggerSheet.getRange("C" + row).setValue(tag); // tag
    dataLoggerSheet.getRange("D" + row).setValue(value); // value
 
 
    // Update summary sheet
    summarySheet.getRange("B1").setValue(dateTime); // Last modified date
    // summarySheet.getRange("B2").setValue(row - 1); // Count 
  }
 
  catch(error) {
    Logger.log(JSON.stringify(error));
  }
 
  Logger.log("--- save_data end---"); 
}

So how you connected the MFRC522 & the SSD1306 ? Because how i understand it, your board is now an ESP-01 (with USB connected to RX & TX) Which does not have the SPI pins exposed, and only has 2 GPIO pins left.