Bad Service

Purchased two Groupon deals, arrive at establishment get told to wait by acting manager. Upon his return he says they do not have stock of the items and that it is valid for Monday to Thursday only. The coupon clearly states Monday to Saturday. The place was completely empty yet my husband, 3year old child and I are turned away. What happened to a substitution or replacement or anything yet they already have our money from the Groupon deals. He just told us the Boss said there is no stock then when I asked may we speak to the Boss suddenly they are not there. I have never encounted such BAD service ever.