WRONG ITEM DELIVERED

I ordered an item via Groupon 19 July 2015. The WRONG item was delivered on 28 July. I advised Groupon on the 29th July of the wrong item. It is now the 12 August - 2 weeks later. I still have not had a response from Groupon on when the correct item will be delivered and the wrong one collected. The call centre operators ARE USELESS AND VERY UNHELPFUL and just keeps blaming the supplier...