See Request of WWW or UnityWebRequest, 403 error only from android in a specific url (GET)

Hello, I have a code that downloads data from a url. I have a problem that one Url gives me error 403 (Forbidden) only from android. When i get the url from editor or Windows build, all works perfectly.
So if i could see the Request that WWW or UnityWebRequest does from android and Windows i would be able to compare whats going wrong.

I tested it with two codes ( WWW and UnityWebRequest) and both give the same result.
i tested it with other urls that contains xml, and it works.

Url: http://www.mambiente.madrid.es/opendata/horario.xml

WWW

IEnumerator DownloadXml(string url, DateTime data = new DateTime())
    {

        WWW www = new WWW(url);
        yield return www;

        ParseXML text = new ParseXML();
        string file = www.text;

UnityWebRequest

IEnumerator GetRequest(string url, DateTime data, bool actualPolution)
    {
        using (UnityWebRequest webRequest = UnityWebRequest.Get(url))
        {
            // Request and wait for the desired page.
            yield return webRequest.SendWebRequest();

            if (webRequest.isNetworkError)
            {
                Debug.Log(url + ": Error: " + webRequest.error);
            }
            else
            {
                ParseXML text = new ParseXML();
                string file = webRequest.downloadHandler.text;
                Debug.Log(url + ":

Received: " + file);

after some test i have managed to retrieve the server data, had to add the accept info this code is tested and works for that site: (i have found a lot of different issues with sites from the Comunidad de Madrid)

    CookieContainer cookies = new CookieContainer();
    HttpWebRequest webRequest = (HttpWebRequest)HttpWebRequest.Create("http://www.mambiente.madrid.es/opendata/horario.xml");
    webRequest.UserAgent = @"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.106 Safari/537.36";
    webRequest.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8";
    webRequest.Method = "GET";
    webRequest.CookieContainer = cookies;
    XmlDocument xmldoc = new XmlDocument(); 
    using (HttpWebResponse webResponse = (HttpWebResponse)webRequest.GetResponse())
    {
        using (StreamReader streamReader = new StreamReader(webResponse.GetResponseStream()))
        {
            string xml = streamReader.ReadToEnd();
            xmldoc.LoadXml(xml);
        }
    }

You should debug your android app, use logcat (for example, in Android Studio).

I suspect it to be related to the CORS problems.
Make sure your server respond with: Access-Control-Allow-Origin:* header