Guaranteed delivery - not guaranteed

Paid for guaranteed Sunday delivery, Its Monday and have not received the items I needed for a client function today. That is why I paid for guaranteed delivery. I have called customer care 3 times since sunday morning, but still no positive feedback. Its now scheduled for Thursday... 4 days after I needed it. Customer care cant assist because its a warehouse issue and the warehouse is not getting back to them so basically the only thing that is guaranteed is that I have to take this one on the chin!