4.2 inch E paper display with arduino Uno does not show anything

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Hello,
I am trying to use Arduino Uno with 4.2 inch E paper to display. The connection is as follows
|e-Paper|Arduino UNO|

|Vcc|3.3V
|GND|GND|
|DIN|D11|
|CLK|D13|
|CS|D10|
|DC|D9|
|RST|D8|
|BUSY|D7|

I followed this link and tried to run the code of looping through integers to show real-time updating. This code was meant for 1.54 inch display, I changed the header file in my code for 4.2 inch display. I used library from waveshare.

The code I am using, is given below

/***************************************************************************
* Arduino e-Paper Text Display on Arduino
*  -- looping through integers to show real-time updating
*
* 
*  by Josh Hrisko | Maker Portal LLC (c) 2021
* 
* 
***************************************************************************/

#include <SPI.h>
//#include "1_54in_epaper.h"
#include "epd4in2.h"
#include <stdlib.h>
#include "epdpaint.h"
#include "imagedata.h"

Epd epd; // initiate e-paper display [epd]
unsigned char image[1500]; // memory for display
Paint paint(image,400, 28); // setup for text display

#define COLORED     0 // background color handler (dark)
#define UNCOLORED   1 // background color handler (light)

int iter_val = 0; // storage variable for serial data

int initial_space = 10; // initial white/dark space at the top of the display
int row_line = 3; // counting rows to avoid overlap
int row_height = 24; // row height (based on text size)

void setup() {
  Serial.begin(9600); // start serial handling for text input 

  epd.Init(); // initialize epaper
  epd.ClearFrame(); // clear old text/imagery
  //epd.DisplayPartBaseWhiteImage(); // lay a base white layer down first

}

void loop() {     
  String str_to_print = "Val: "; // string prepend
  str_to_print+=String(iter_val); // add integer value
  
  header_print(); // print header text
  
  paint.Clear(UNCOLORED); // clear background
  paint.DrawStringAt(0, 4, str_to_print.c_str(), &Font20, COLORED); // light background
  epd.SetPartialWindow(paint.GetImage(), 0, initial_space+(3*row_height), paint.GetWidth(), paint.GetHeight());
  //epd.DisplayPartFrame(); // display new text
  epd.DisplayFrame(); // display new text
  iter_val+=1; // increase integer value
}

void header_print(){
  paint.SetWidth(200); // set display width
  paint.SetHeight(24); // set initial vertical space
  
  paint.Clear(COLORED); // darkr background
  paint.DrawStringAt(0, 4, "1.54in e-Paper!", &Font20, UNCOLORED); // light text
  epd.SetPartialWindow(paint.GetImage(), 0, initial_space+(0*row_height), paint.GetWidth(), paint.GetHeight());

  paint.Clear(UNCOLORED); // light background
  paint.DrawStringAt(0, 4, "Simple Demo", &Font20, COLORED); // dark text
  epd.SetPartialWindow(paint.GetImage(), 0, initial_space+(1*row_height), paint.GetWidth(), paint.GetHeight());

  paint.Clear(COLORED); // dark background
  paint.DrawStringAt(0, 4, "Maker Portal", &Font20, UNCOLORED); // light text
  epd.SetPartialWindow(paint.GetImage(), 0, initial_space+(2*row_height), paint.GetWidth(), paint.GetHeight());
}

But once I run the code , display does not show anything. There is no error message.

I do not understand the problem. Could anyone please help?

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