Not will to pay out Credit

I was bought items as a present from the hub on the 28/11/2014,My wife don't have the slip and I also dont have it hence present, Unfortunately the items is not what I would where and I need a refund, I contact Greenstone <br> Its and been up and down twice its the second day. I specifically advised them I dont not want more credit just a refund. I dont wanna but anything from the HUB,<br> I email them twice and I emailed head office dismal replies been dealing with Manager Sonja, This till slips are duplicated and confirmation of every bar code scanned is send to head office,. This is how you keep track of every purchase that goes through the system.<br> I provided them with all information require but to no satisfaction, please can I have my refund I did not want to go as far as this.<br>