Changing/Creating password through SQL

Hey Guys,
So I’m making an application that integrates with wordpress database. Using php, I connect to my remote database (as i dont own the server). I’m able to update and create all records of a user except for the password. The php/sql code i use to create a new user is

<?PHP
$dbhost = 'host';
$dbuser = 'user';
$dbpass = 'password';
$user= $_GET['user'];
$pass=$_GET['pass'];
$name= $_GET['name'];
$email= $_GET['email'];
$sex= $_GET['sex'];
$conn = mysql_connect($dbhost, $dbuser, $dbpass) or die                      ('Error connecting to mysql');
$dbname = 'databasename';
mysql_select_db($dbname);
$query="INSERT INTO wp_users (user_login, user_pass, user_nicename, user_email, user_registered, display_name, user_sex)
VALUES ('$user', MD5('$pass'), '$user', '$email', NOW(), '$name', '$sex')";
?>

I pass these variables to the php file using URL. Since password in the table is encrypted I had used MD5 for encryption. To update the password through phpMyAdmin I had to use MD5 function so I tried to use the same logic for even creating/updating a password. The sql code that works with phpMyAdmin is

UPDATE wp_users SET user_pass = MD5('password') WHERE  ID =1;

You can see I used the same logic! But its still not working. Any help is greatly appreciated.