Trying to download a memorystream in my web api but i don't get the content

OK, so i try to download a memorystream with data in it, i already know the byte array i convert it to has the data in it but i dont get why my response isn't working. Wenn i press the button on the website nothing happens (well something happens, but i don't get the download...). I think all the HTTP headers must be correct, after all the research i couldnt find anything more than that.

using System.IO;
using System.Web;
using System.Net.Http;
using System.Net.Http.Headers;


namespace TranslationManager.Controller
{
    [Route("api/controller")]
    [ApiController]
    public class Download : HttpGetAttribute
    {

       [HttpGet]
       public HttpResponseMessage File(MemoryStream ms)
        {
            byte[] b = ms.ToArray();

            
            var response = new HttpResponseMessage(System.Net.HttpStatusCode.OK);

            response.Content = new ByteArrayContent(b);

            //Set the Response Content Length.
            response.Content.Headers.ContentLength = b.LongLength;

            //Set the Content Disposition Header Value and FileName.
            response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
            response.Content.Headers.ContentDisposition.FileName = "file";
            response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");

            return response;
        }
    }

}