为什么在C#和PowerShell中使用完全相同的代码加密HMAC-SHA1会显示不同的结果？

using System;
using System.Security.Cryptography;
using System.Text;

class Program
{
    static void Main()
    {
        string key = "your_key";
        string message = "your_message";

        byte[] keyBytes = Encoding.UTF8.GetBytes(key);
        byte[] messageBytes = Encoding.UTF8.GetBytes(message);

        using (HMACSHA1 hmac = new HMACSHA1(keyBytes))
        {
            byte[] hashBytes = hmac.ComputeHash(messageBytes);
            string hash = BitConverter.ToString(hashBytes).Replace("-", "").ToLower();
            Console.WriteLine(hash);
        }
    }
}

$key = "your_key"
$message = "your_message"

$keyBytes = [System.Text.Encoding]::UTF8.GetBytes($key)
$messageBytes = [System.Text.Encoding]::UTF8.GetBytes($message)

$hmac = New-Object System.Security.Cryptography.HMACSHA1($keyBytes)
$hashBytes = $hmac.ComputeHash($messageBytes)
$hash = [System.BitConverter]::ToString($hashBytes).Replace("-", "").ToLower()
Write-Output $hash