Error Code 0x80070002 when debugging C++ in VS19

I'm very very new to coding C++ I'm learning OOP in C++ and I was trying to write a program on my own

    class Account
    {
    private:
        string name;
        double balance;
    public:
        Account();
        Account(string name_val);
        Account(double bal_val);
        Account(string name_val, double bal_val);
    };

That's the class

Account::Account(): name { "None" }, balance{ 0.0 }{}
Account::Account(string name_val) : name{ name_val }, balance{ 0.0 }{}
Account::Account(double bal_val) : name{ "None" }, balance{ 0.0 }{}
Account::Account(string name_val, double bal_val) : name{ name_val }, balance{ bal_val }{}

These are the declarations that I did

Account empty;
    Account frank{ "Frank" };
    Account rich_boi{ 1000000.0 };
    Account sad_boi{ "Sad boi", -10.0  };

These are the objects I made in main

Edit: I also did one program(which I got from a udemy course) before this which worked perfectly This was the class

class Player
{
private:
    string name;
    int health;
    int xp;
public:
    //Overloaded Constructors
    Player();
    Player(string name_val);
    Player(string name_val, int health_val, int xp_val);
};

These were the constructors

Player::Player() : name{ "None" }, health{ 0 }, xp{ 0 }{}

Player::Player(string name_val) : name{ name_val }, health{ 0 }, xp{ 0 }{}

Player::Player(string name_val, int health_val, int xp_val) : name{ name_val }, health{ health_val }, xp{ xp_val }{}

And these were the objects in main

    Player empty;
    Player frank{ "Frank" };
    Player villain{ "Villain" , 100 , 55 };

 Account::Account(): name ( "None" ), balance( 0.0 ){}

 Account::Account(string name_val) : name( name_val ), balance(0.0 ){}

 Account::Account(double bal_val) : name("None" ), balance(bal_val ){}

 Account::Account(string name_val, double bal_val) : name( name_val ), balance( bal_val ){}

That should be the correct definition of your class constructors.

Account empty;
Account frank("Frank" ); 
Account rich_boi( 1000000.0 );  
Account sad_boi( "Sad boi", -10.0 );

And that's how you should declare your objects in the main() of your program. You syntax was incorrect.

The correct syntax of initialisation list in C++ is :

Constructorname(datatype value1, datatype value2):
                   datamember(value1),
                   datamember(value2) {
                  .
                  . //Anything if at all you want to include in your constructor function
                  . 
}