I have a url that requires authentication to access the link. I am trying to download the data to a stream as follows:

        var url =  representations.Entries.FirstOrDefault().Info.Url.ToString();
        
        try{
            using (var httpClient = _httpClientFactory.CreateClient())
            {           
                httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", await token.FetchTokenAsync());
 
                using (var memoryStream = new MemoryStream())
                {
                    var stream = await httpClient.GetStreamAsync(url);
                    (stream).CopyTo(memoryStream);
                    memoryStream.Position = 0;

                    byte[] buffer = new byte[memoryStream.Length];
                    await memoryStream.ReadAsync(buffer, 0, (int)memoryStream.Length);
                    return Convert.ToBase64String(buffer);
                }
            }
        } catch (Exception ex)
        {
            return "";
        }

At the line where I load the stream from httpClient it states the following for various aspects of the stream:

Specified method is not supported.