Switch statemement reacting wrong after method getline c++ - c++

Question

I am coding a banking app for university and i have stumbled upon a problem. Let's take for example a method of my class Customer.
void Customer::create_customer_data() {
cout << "Client' Address: ";
getline(cin, clientAddress);
cin.ignore();
cout << "Client's birth date: ";
getline(cin, clientBirthDate);
cin.ignore();
cout << "Client's telephone number: ";
getline(cin, clientTelephoneNumber);
cin.ignore();
cin.clear(); }
In the main function, i have a switch statement which handles the user choice.
int main() {
int choice, _globalClientNumber = 0;
Customer a(_globalClientNumber);
cout << "Welcome to bank manager 1.0!" << endl;
do {
cout << "Main Menu"<< endl;
cout << "Create a new customer (1)" << endl;
cout << "Create a new account (2)" << endl;
cout << "Cash money into account (3)" << endl;
cout << "Cash money out of account (4)" << endl;
cout << "Transfer money between two accounts (5)" << endl;
cout << "See current status of a customer and its accounts (6)" << endl;
cout << "End Application (0)" << endl;
cout << "Choice: ";
cin >> choice;
switch (choice) {
case 1:
a.create_customer_data();
break;
case 2:
a.create_new_account();
break;
case 3:
a.cash_in();
break;
case 4:
a.cash_out();
break;
case 5:
a.transfer_money();
break;
case 6:
a.print();
break;
default:
break;
}
cout << endl;
}
while (choice != 0);
return 0; }
The problem that i keep having is that the values that are written on the screen by the create_customer_data method are being processed by the do-while loop. So if the clientTelephoneNumber in the create_customer_data does not end in 0, the main menu is shown twice by the do-while loop. I would appreciate it if someone could tell me where my mistake is.
Edit: Shortly said: the choice variable gets overridden and the do-while loop gets executed once more resulting in double printing the menu.

Answer 1

i would say, that your cin needs to be flushed.
the answer can be found here:
How do I flush the cin buffer?