ATM Cash Withdrawal in C program

#include<stdio.h>
#include<conio.h>
unsigned long amount=25000, deposit, withdraw;
int choice, pin, i;
char transaction ='y';
void main()
{
clrscr();
while (pin != 1097)
{
printf("ENTER YOUR PIN NUMBER: ");
scanf("%d", &pin);
if (pin != 1097)
printf("PLEASE ENTER VALID PASSWORD\n");
}
do
{
printf(" Welcome to ATM Service \n");
printf("1. Check Balance\n");
printf("2. Withdraw Cash\n");
printf("3. Deposit Cash\n");
printf("4. Quit\n");
printf("\n\n");
printf("Enter your choice: ");
scanf("%d", &choice);
switch (choice)
{
case 1:
printf("\n YOUR BALANCE =Rs.%lu ", amount);
break;
case 2:
printf("\n ENTER THE AMOUNT: ");
scanf("%lu", &withdraw);
if (withdraw % 100 != 0)
{
printf("\n PLEASE ENTER THE AMOUNT IN MULTIPLES OF 100");
}
else if (withdraw >(amount - 1000))
{
printf("\n INSUFFICENT BALANCE");
}
else
{
amount = amount - withdraw;
printf("\n\n PLEASE COLLECT YOUR CASH");
printf("\n YOUR CURRENT BALANCE =RS.%lu", amount);
}
break;
case 3:
printf("\n ENTER THE AMOUNT: ");
scanf("%lu", &deposit);
amount = amount + deposit;
printf(" YOUR BALANCE =RS.%lu", amount);
break;
case 4:
printf("\n THANK YOU USING OUR ATM SERVICES");
break;
default:
printf("\n INVALID CHOICE");
}
printf("\n\n\n DO U WISH TO HAVE ANOTHER TRANSCATION?(y/n): ");
fflush(stdin);
scanf("%c", &transaction);
if (transaction == 'n'|| transaction == 'N')
i = 1;
} while (!i);
printf("\n\n THANKS FOR USING OUR ATM SERVICE");
getch();
}

Output-1:

Output-2:

Output-3: