Group On Not responding to queries

I just want to express my disapointment on Groupon. I have been shopping on Group on for some time now and never experinced this until recently. I purchased two seperate items on groupon about a month ago. I had to cancell one order as i no longer could utilise, i have been dealing with them regarding a refund for the past 3 weeks and to date i have not received my money. My major concern is the second order which i paid for and put the correct reference number but 4 days after i had paid, instead of dispalying the voucher number it jsut dissapeared, i have been sending emails, trying to call to find out what happened to this item as i had paid for and sent through proof of payment. To this day, no one has bothered replying from Group on. Everytime i call, i'm always assgned some ridiculous number on the Q.