Not living up to their promises

I purchased a mattress on Sunday the 8th of March 2015 and paid for the delivery thereof. I was promised delivery on the 11th. Indicating the importance of the delivery, I have a back problem) I am still waiting for the delivery to take place. This after I called the store 3 times during the day on Thursday the 12th. I think it is bad manners and poor customer service to promise knowing you cannot deliver and or keep to your promises.