Avoid this company!

My order was placed for two items via Groupon. One item was delivered late, the other not delivered. I queried this, they apologised and said they would send it. Another long wait, and they sent the first item again. I contacted them and they promised to deliver the second item and collect the first one. Another wait, then a courier collected the duplicate item, but no delivery. Since then I have contacted them repeatedly, asked for a refund of the item not delivered, but only get automated replies.