False promotional information and lack of interest in customers

I received a promotional email of a shoe/sneaker that said -86% when I put it in my cart it only deducted 50% .I have been in correspondence with superbalist since 2nd April,to date I have not received any assurance that I would get the shoe for the price it was advertised. At any store you walk in to you pay the price that is advertised to you.What makes matters worse is that this was emailed to me I did not just come accross a ad on Google. By the time you guys respond to me,what if my size is no longer available? The communication and management of my query was very unprofessional from your side.