public function getUserByEmailAndPassword($email, $password) {

       $sql = "SELECT * FROM users WHERE email = ?"; // SQL Statement
       $stmt = $this->conn->prepare($sql); // Prepare the SQL Statement
       $stmt->bind_param('s', $email); // Bind the placeholder with the correct data type from the SQL Statement
       $stmt->execute(); // Execute the prepared statement
       $stmt->store_result(); // Store the prepared statement for later checking

       // Check to make sure if any data is returned
       if($stmt->num_rows) {

           // Create and append variables
           $user = $stmt->bind_result($email);


          // Create a while loop
           while($stmt->fetch()) {
              // verifying user password
              $salt = $user['salt'];
              $encrypted_password = $user['encrypted_password'];
              $hash = $this->checkhashSSHA($salt, $password);
              // check for password equality
              if ($encrypted_password == $hash) {
                 // user authentication details are correct
                 $stmt->close();
                 return $user;
              }else {

            }
        }
            return NULL;
    }
}