No one wants to help

I placed an order on the 23/04/2015.I recieved the incorrect item. I notified groupon and they told me they will get the incorrect item picked up and drop of the correct item.they eventually picked it up on Monday the 11/05/2015 after a week of waiting. I have not received my item as yet. I called the call centre they told me to send an email to the supplier which I did. I have yet to receive a response and groupon asked me to wait another day. I asked if I could get refund and was told its not possible to get a refund. It been 3 weeks and Im annoyed that no one wants to assist me.everyone just passes the buk to the next person and no one wants to take responsibility.its highly frustrating. Its unproffessional