มันกดจอง ได้ ข้อมูล เข้าฐาน แต่จำนวนห้องมันไม่ลด พี่ ๆ ช่วยดูทีครับ

<?php
			if (isset($_POST['date_start']) && isset($_POST['date_end'])) {
				if (!empty($_POST['date_start']) && !empty($_POST['date_end'])) {
					$count_rooms = $db->select("SELECT * FROM rooms WHERE room_name = 'Deluxe'");
					$check_rooms = $db->select("SELECT * FROM reservation WHERE (date_start BETWEEN '".$_POST['date_start']."' AND '".$_POST['date_end']."' OR date_end BETWEEN '".$_POST['date_start']."' AND '".$_POST['date_end']."') AND room = 'Deluxe'");
					$sum_rooms = $count_rooms[0]['room_quantity'] - $check_rooms[0]['h_room'];
					
				//	echo 'cnt room '.$count_rooms[0]['room_quantity'].'--';
				//	echo 'check room '.$check_rooms[0]['h_room'].'--';
						
						if ($sum_rooms > 0) {
							echo $sum_rooms;
							echo "<input type='hidden' name='date_start' value='".$_POST['date_start']."' />";
							echo "<input type='hidden' name='date_end' value='".$_POST['date_end']."' />";
							echo "<input type='hidden' name='t_room' value='".$_POST['t_room']."' />";
							echo "<input type='hidden' name='t_ad' value='".$_POST['t_ad']."' />";
							echo "<input type='hidden' name='t_ch' value='".$_POST['t_ch']."' />";
							echo "<input type='hidden' name='room' value='Deluxe' />";
						} else {
							echo "ไม่ว่าง";
						}
				}
			}
			?>