Unity WebGL build and PHP Post communication

Hello, I am working on Unity Web-game and has a problem only in WebGL-build version uploaded to my server. On SendData Method I'm getting empty string as result.But in editor all ok.

My PHP looks like this:

 <?php
 
 header("Access-Control-Allow-Credentials: true");
 header("Access-Control-Allow-Origin: *");
 header("Access-Control-Allow-Methods: POST");
 header("Access-Control-Allow-Headers: Accept, X-Access-Token, X-Application-Name, X-Request-Sent-Time");
 
 $score = $_POST["Score"];
 
 $filePath = "dataValue.txt";
 $content="0";
 if(filesize($filePath) >0)
 {
     $handler1 = fopen($filePath,'r');
     $content = fread($handler1,filesize($filePath));
     fclose($handler1);
 }
 
 
 if((int)$score<(int)$content)
 {
     $handler2 = fopen($filePath,'w+');
     fwrite($handler2,$score);
     fclose($handler2);
 }
 else {
 }
 
 
 ?>

And C# Method:

 public IEnumerator SendData(string data)
     {
         sendCoroutine = true;
         // if(data==String.Empty)
         //     data = textField.text;
     
         WWWForm form = new WWWForm();
         form.AddField("Score",data);
         WWW w =new WWW(url+"data.php",form);
 
         yield return w;
 
         if (w.error != null)
         {
             Debug.Log("Not Response");
         }
         else
         {
             Debug.Log("Response text: "+w.text);
             //text.text = w.text.ToString();
         }
         
         w.Dispose();
         sendCoroutine = false;
     }

First Try Was No Using Headers, but and with them I dont get desired result... What a problem may be here? Thanks you for answers! I really need it!