Unable to append text file - c++

Question

I am creating a hotel management system. In the book_room function the user enters a room number , the control shifts to the check function and if the room is available then it asks for some details and then books the room.
Now so that multiple rooms can be displayed in the file, I added the app mode to append the file however due to this the program didn't take input at all.
#include <iostream>
#include <conio.h>
#include <fstream>
#include <stdio.h>
#include <stdlib.h>
#include <dos.h>
#include <string>
using namespace std;
struct hotel {
int room_no[51];
string name[51];
string adress[51];
int mobile_no[51];
int bill[51];
int days[51];
int room;
int room1;
int flag = 0;
fstream records;
void main_menu();
int book_rooms();
int customer_records();
int rooms_alloted();
int edit_records();
int customer_bills();
int check(int);
};
void hotel::main_menu()
{
int choice;
while (choice != 6) {
system("cls");
cout << "\n\t\t\t\t*************************";
cout << "\n\t\t\t\t HOTEL MANAGEMENT SYSTEM ";
cout << "\n\t\t\t\t * MAIN MENU *";
cout << "\n\t\t\t\t*************************";
cout << "\n\n\n\t\t\t1.Book A Room";
cout << "\n\t\t\t2.Customer Records";
cout << "\n\t\t\t3.Rooms Allotted";
cout << "\n\t\t\t4.Edit Record";
cout << "\n\t\t\t5.Customer Bills";
cout << "\n\t\t\t6.Exit";
cout << "\n\n\t\t\tEnter Your Choice: ";
cin >> choice;
switch (choice) {
case 1: {
book_rooms();
break;
}
case 2: {
customer_records();
break;
}
case 3: {
rooms_alloted();
break;
}
case 4: {
edit_records();
break;
}
case 5: {
customer_bills();
break;
}
case 6: {
break;
}
}
}
}
int hotel::book_rooms()
{
int i = 1;
char yes = 'y';
while (yes == 'y') {
system("cls");
int room;
cout << "\n\t*************************";
cout << "\n\t ROOM BOOKING";
cout << "\n\t*************************";
cout << "\n\nPlease enter the room number you want to book.";
cout << "\n1: Standard room(Room 1-20) (Rs.1000/night)";
cout << "\n2.Suite(Room 21-40) (Rs.5000/night)";
cout << "\n3.Luxury Room(Room 41-50) (Rs.10000/night)\n";
cin >> room;
flag = check(room);
ofstream records{ "rooms.txt", ios::app };
if (flag == 1) {
cout << "Sorry this room has been taken";
system("pause");
}
else {
cout << "\n";
room_no[room - 1] = room;
records << "Room " << room_no[room - 1] << "\n";
cout << "Name:";
getline(cin, name[room - 1]);
getline(cin, name[room - 1]);
records << name[room - 1] << "\n";
cout << "Adress:";
getline(cin, adress[room - 1]);
records << adress[room - 1] << "\n";
cout << "\nMobile no: ";
cin >> mobile_no[room - 1];
records << mobile_no[room - 1] << "\n ";
cout << "\nYour room has been booked\n";
cout << "Do you want to book another room\n";
cin >> yes;
}
}
system("pause");
records.close();
}
int hotel::check(int r)
{
flag = 0;
ifstream records("rooms.txt");
while (!records.eof()) {
records >> room_no[r - 1];
if (room_no[r - 1] == r) {
flag = 1;
break;
}
}
records.close();
return flag;
}
int main()
{
hotel p;
p.main_menu();
}