"If while" statements problem

[pratto123]

When I run this program, it lets me enter in all the variables, but then it starts a new line and won't do anything else. Not sure what the deal is.

  #include <iostream>
using namespace std;
int main ()
{
	double months=0, beginning_balance, interest_rate, set_payment_amount, new_balance;
	cout << "Enter your account balance.";
	
	cin >> beginning_balance;
	
	cout << "Enter the interest rate.";
	
	cin >> interest_rate;
	
	cout << "Enter your monthly payment amount.";
	
	cin >> set_payment_amount;
	while (new_balance > 0)
	{
		new_balance=beginning_balance+beginning_balance*interest_rate-set_payment_amount;
		months=months+1;
	}
	cout << "Total number of months needed to pay off debt is ";
	cout << months << "\n";
	
return 0;
}