UnityWebRequest: Null response

Question

So I have a website(it is unsecured/it doesn't have an SSL certificate) where I have a php script that echo's some info of my database. Here is it:

$query = "SELECT id, password FROM users WHERE username = ".$_GET['uname'];
$result = mysqli_query($connect, $query);

while( $record = mysqli_fetch_assoc($result) )
{
    echo json_encode($record);
}

Now, in Unity(version 2022.1.0b10.2818), I have a script that does a get request to my website and gets the info the php script displayed. Here is the script:

IEnumerator GetText()
{
    string url = "http://example.com/getUser.php?uname=" + "'" + 
    usernameInputField.text + "'";

    using(UnityWebRequest www = UnityWebRequest.Get(url))
    {
        yield return www.SendWebRequest();

        if(www.result != UnityWebRequest.Result.Success)
        {
            Debug.Log(www.error);
        }
        else
        {
            response = www.downloadHandler.text;
        }
    }
}

Why does it always give me this error:

Curl error 52: Empty reply from server

and I also get this log in the console from the Debug.log(ww.error):

Received no data in response How can I fix this?