I WANT MY REFUND. PAY BACK THE MONEY

I bought 2 pairs of dvd screens from groupon only to find that one of the screens was defective. Firstly the process of returning the product took too long due to groupon not replying to my emails and not sending a courier to collect the screens. Finally they fetched the screens, then I was told I would receive my refund, this I was told on 17 Feb. The refund never happened after the 4-5 working days they said. Then I had to email my credit card statement to prove I haven't received the refund. I was then told the refund was processed but it was the banks fault. Then on 9 March I was told that the bank will have the refund reprocessed, please allow up to 10 working days for the funds to reflect. It is now 1 April 2016 (14 working days) and I am still waiting on my refund for a product that was bought in 2015. This level of customer service is unacceptable and appalling. I will think twice next time when buying something from groupon next time, especially if it's an electrical product. I JUST WANT MY REFUND BACK. PAY BACK THE MONEY.