Groupon refuses to refund

Good day. I recently bought a Groupon voucher for a hair treatment. The treatment was for a hair cut and a Cacau Brazilian Blow out. I phone the salon to make the appointment and I am advised that because i am allergic to nuts that I am not able to have this treatment. I email support at groupon and was sent a general email that someone would contact me in two days. Two days go by and nothing. I get another email from Groupon saying that they are experiencing high volume of emails and someone will contact me. Two weeks later and still no one contacted me, so I phoned only to be told that I need to get a letter from the salon saying that I can't have the treatment because of my nut allergy. Nonsense! You are suppose to do that not me. It did not say in the fine print that if i had a nut allergy i must not buy the voucher. Someone needs to contact me to sort this out. I want a refund to purchase something else on your site. I have been waiting two weeks for a response and want this sorted out before the end of the week,