Bad & nusty service @ game

Bad service at game mall@reds my mother bought a fridge 2 months back, they told her that they don't have stock they will call her when they received stock from their supplier, we waited and Waited they didn't call, until I decided to call them and still they say no stock. My mom went there 2weeks ago to ask them about the, they told her that they can't find her on the system she must come with the slip so they can check, now she went there with the slip they told her that the fridge was collected.... What must we do now?