function insert_employee() {
  global $con;
  if (isset($_POST['insert_post'])) {
        $fname = $_POST['first_name'];
        $lname = $_POST['last_name'];
        $email = $_POST['email'];
        $type = $_POST['type'];
        $username = $_POST['username'];
        $password = $_POST['password'];

       if ($fname == '' || $lname == '' || $email == '' || $type == '' || $username == '' || $password == '' ) {
           echo 'please fill all values';
       } else {

           $sql = "INSERT INTO users (username, password) VALUES ('$username', '$password')";
           mysqli_query($con, $sql);

           $id = mysqli_insert_id($con);

           if ($id) {
               $sql = "INSERT INTO employee (fname, lname, email, type, user_id) VALUES ($fname, $lname, $email, $type, $id)";
               mysqli_query($con, $sql);
           }
       }
       mysqli_close($con);
   }
   echo "Data Inserted";
}