Find 3 different strings that have the same hash code

 C#, write a method :
public static List<string> FindStringsWithMatchingHashcodes()
 that will produce 3 different System.String objects (different string values) that have the same hash code such that none of the resulting String objects have the same value. 
Note 1: you dont need to know GetHashCode implementation details, you dont need to override GetHashCode anywhere and you must not create your own String classes. 
Note 2: Only strings with displayable characters will be considered. 
Note 3: the usage of multithreading is not required for this exercise.

using System;
using System.Collections.Generic;
public class HashCollisionFinder
{
    
    public static List<string> FindStringsWithMatchingHashcodes()
    {
        var hashDict = new Dictionary<int, List<string>>();
        var passedStr = new HashSet<string>();
        var rand = new Random();
        int length = rand.Next(3, 15);

        while (true)
        {
            string candidate = GenerateRandomStr(rand, 4);
            if (!passedStr.Add(candidate))
                continue;
            int hash = candidate.GetHashCode();
            if (!hashDict.TryGetValue(hash, out var list))
            {
                list = new List<string>();
                hashDict[hash] = list;
            }
            list.Add(candidate);
            if (list.Count == 3)
                
                return list;
        }
    }
    private static string GenerateRandomStr(Random rand, int length)
    {
        char[] buffer = new char[length];
        for (int i = 0; i < length; i++)
        {
            buffer[i] = (char)rand.Next(32, 127); // characters from ASCII table
        }
        return new string(buffer);
    }
    public static void Main()
    {
        List<string> result = FindStringsWithMatchingHashcodes();
        Console.WriteLine("Three different strings with the same hash code:");
        foreach (string str in result)
        {
            Console.WriteLine($"{str} -> HashCode: {str.GetHashCode()}");
        }
    }
}