Retvlei Voucher-Unable to receive my voucher

Good day. On the 28 December 2015 I bought Retvlei Voucher on Groupon for R291.00 for 4 people until today I have not received my Voucher. I contacted Groupon on the 4th January 2016 by email and they said they will get back to me after 2 days until today I am still waiting. Please assist