Register help

So i'm working with unity and mySQL database and Php. I need it to insert data into the database from this code. It works with connecting to database and all, checks if fields are empty and the check if it(email/username) already exists works. But when it is available it doesn't work.

For obvious reason is censored all the import stuff like connection names and such using

Php code here

 <?
 // CONNECTIONS =========================================================
 $host = "localhost"; //put your host here
 $user = "*******"; //in general is root
 $password = "******"; //use your password here
 $dbname = "*****"; //your database
 mysql_connect($host, $user, $password) or die("Cant connect into database1");
 mysql_select_db($dbname)or die("Cant connect into database");
 // =============================================================================
 $unityHash = $_POST["myform_hash"];
 $phpHash = "********"; 
  
 $nick = $_POST["myform_nick"];
 $pass = md5($_POST["myform_pass"]); // md5 hashes the password
 $email = $_POST["myform_email"];
  
 if(!$nick || !$pass || !$email)
 {
     echo "Login, password, or email cant be empty.";
 }
 else
 {
     if ($unityHash != $phpHash)
     {
         echo "HASH code is different from your game, you infidel.";
     }
     else
     {
         $checkuser = mysql_query("SELECT name FROM scores WHERE name='$nick'");
         $username_exist = mysql_num_rows($checkuser);
         $checkemail = mysql_query("SELECT email FROM scores WHERE email='$email'");
         $email_exist = mysql_num_rows($checkemail);
         if($username_exist > 0)
         {
               echo "Sorry but the username you specified has already been taken.  Please pick another one.";
               unset($nick);
               exit();
         }
         if($email_exist > 0)
         {
             echo "Sorry but the email is already in use. Please use another one.";
             unset($email);
                 exit();
         }
         if($username_exist = 0 && $email_exist = 0) // This is the part that doesn't work...
         {
             $query = "INSERT INTO scores (id, name, password, email, balance, level, xp, wins, loses) VALUES (NULL, '$nick', '$pass', '$email', '0', '0', '0', '0', '0');";
             echo "You have successfully Registered";
            
         }
        
     }
 }
 mysql_close();
 ?>

and this is the Javascript code inside unity.

 #pragma strict
 private var formNick = ""; //this is the field where the player will put the name to login
 private var formPassword = ""; //this is his password
 private var formEmail = ""; //this is his email
 var formText = ""; //this field is where the messages sent by PHP script will be in
  
 var URL = "http://*********.com/*******.php";
 var hash = "*********"; 
  
 private var textrect = Rect (10, 150, 500, 100); //just make a GUI object rectangle
  
 function OnGUI() {
     GUI.Label( Rect (10, 10, 80, 20), "Your Email:" ); //text with your nick
     GUI.Label( Rect (10, 30, 80, 20), "Your Name:" );
     GUI.Label( Rect (10, 50, 80, 20), "Your Pass:" );
  
     formEmail = GUI.TextField ( Rect (90, 10, 100, 20), formEmail ); //here you will insert the new value to variable formNick
     formNick = GUI.TextField ( Rect (90, 30, 100, 20), formNick ); //same as above, but for password
      formPassword = GUI.TextField ( Rect (90, 50, 100, 20), formPassword );
  
     if ( GUI.Button ( Rect (10, 90, 100, 20) , "Register" ) ){ //just a button
         Register();
     }
     if ( GUI.Button ( Rect (110, 90, 100, 20) , "Back" ) )
     {
         Application.LoadLevel("Menu_Login");
     }
     GUI.TextArea( textrect, formText );
 }
  
 function Register() {
     var form = new WWWForm(); //here you create a new form connection
     form.AddField( "myform_hash", hash ); //add your hash code to the field myform_hash for php
     form.AddField( "myform_nick", formNick );
     form.AddField( "myform_pass", formPassword );
     form.AddField( "myform_email", formEmail );
     var w = WWW(URL, form);
     yield w; 
     if (w.error != null) {
         print(w.error); //if there is an error, tell us
     } else {
         print("Test ok");
         formText = w.data; 
         w.Dispose(); //clear our form in game
     }
 }