We purchased all new flooring from a well-know home store and worked a deal for 20% off. The discount was already in the system, but at checkout they gave us another 20% off, which we did not realize until the store called the next day and said they accidentally gave us 40% off and we need to go in and pay the difference. My question: do we legally have to pay the difference and can they cancel the order if we don't? The flooring has yet to be installed. I appreciate any help as I will be speaking with them today. Thank you!