Having trouble with yes and no loops

So in my computer science class we got to make a lunar lander game. At the very end of the code we are supposed to ask if the user wants to run the game again, while Ive established a yes and no loop, it still doesnt work. It lets me type 'Y' and 'N' but it just breaks right after words.

  // Include Section
  #include <iostream>
  #include <cstdlib>
  #include <iomanip>
  using namespace std;

  // Main Program
  int main( )
  {
   // Variable Declarations
   double E;            // Engine output
   double V;            // Velocity output
   double A;            // Altitude output
   double T;            // Time output
   double F;            // Fuel consumption
   double Th;           // Thrust
   double x;            // The variable output the user puts in
   double G;            // The gravity of the moon
   double Acceleration;// The acceleration found between the force and the    

gravity double M; // Total Mass of the lander double Force; // The force opposing the lunar gravity double W; // Weight double Thrust; // The initial thrust value char Ans;

A=2300;
V=0;
T=0;
F=300;
G=-1.62;
Thrust=43900;
M= 6831;


// Output Identification
system("CLS");

cout << "Welcome to the Lunar Lander simulation!" << endl;
cout << endl;
cout << "You are in command of the Lunar Lander on its final approach to the moon's surface."
    " You need to control the thrust to the main decent engine."
    " You will adjust it each second by typing in the percent thurst that you would like for the next second."
    " Your goal is to end land the spacecraft at a velocity of less than 1 meter/second."
    <<endl;
cout << endl;
cout << "GOODLUCK!"<<endl;
cout << endl;
cout << setw(8) << "Sec" << setw(10) << "Alt" << setw(10) << "Speed" << setw(8) << "Fuel" << endl;

while(F > 0)
{
    if(A > 0)
    {
        cout << setw(8) << T << setw(10) << A << setw(10) << V 
            << setw(8) << F << setw(14) << "     Enter percent burn (0-100):";
        cin >> x;
        if( x < 0|x > 100)
        {
            cout << "Please pick a valid percentage."<< endl;
        }
        else
        {
            T++;
            x=x/100;
            Th= x*Thrust;
            E= 13.6*x;
            F= F-E;
            M =M-E;
            W=M*G;
            Force=Th+W;
            Acceleration=Force/M;
            V=V+Acceleration*1;
            A=A+V*1-.5*Acceleration*1;
        }
    }
    else
    { 
        if(V <= -1 & V >=-3)
        {
            cout << "Congratulations!" << endl;
            cout << "Would you like to run the simulation again? <Y/N>"<<endl;
            cin >> Ans;
            if(Ans == 'Y'|| Ans == 'y')
                return 0;
            else
                break;
        }
        else
        {
            cout << "Game Over" <<endl;
            cout<< "Would you like to run the simulation again? <Y/N>"<<endl;
            cin >> Ans;
            if(Ans == 'Y'||Ans == 'y')
                return 0;
            else
                break;
        }
    }
    if(F<=0)
    {
    cout<< "Would you like to run the simulation again? <Y/N>"<<endl;
    cin >> Ans;
        if(Ans == 'Y'|| Ans=='y')
            return 0;
        else
            break;
    }
}

}