Bad Service

I made an order and their website indicated that my item is available for delivery today. They then called me to say that my item can't be delivered today because they have a high volume of orders and it's not ready. I then ask to speak to a manager because it's important that the item gets delivered as the occasion is today. When I asked why the would then put the date they can deliver and not deliver on the day, they said that their system should have blocked the orders. The consultant said that the managers were all in a meeting and I would get a call back in an hour's time, an hour has passed and still I haven't received a call.