simple random password generator in c#

Program.cs

using System;
using System.Text;
 
public class PasswordGenerator
{

    public static void Main()
    {
        int passwordLength = 15;
        string password = GeneratePassword(passwordLength);
        Console.WriteLine(password);
    }

    public static string GeneratePassword(int length)
    {
        const string characters = "!@#$%^&*()<>?-_=+;:,.0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
 
        var passwordBuilder = new StringBuilder(10, 20);
        var randomNumber = new Random();
 
        for (int i = 0; i < length; i++)
        {
            int index = randomNumber.Next(characters.Length);
            passwordBuilder.Append(characters[index]);
        }
 
        return passwordBuilder.ToString();
    }
}