Never had a problem until today. I had ordered 2 items and applied a discount code that was being advertised on their site at the time. The invoice shows the discount "£12 off" was applied to the whole order. Sadly I had to return one item (the cheaper one) but was refunded only a partial amount. I queried this using their "chat" service. The response was delayed and then short, unhelpful and rude. They said the main part of the order wasn't valid for the voucher but did not explain why, or the terms and conditions of said discount code. When I asked for further clarification as to why a sale item was valid and not a full price one (as their other offers normally say the opposite), they provided a screenshot with the phrase "we have proof". This merely showed the total transaction amount at their end, not evidence that the discount code only applied to refunded item. I pointed this out and they said "you were refunded the correct amount". I gave up after that as it was clearly a waste of time. Even if I have misunderstood the t&cs, the interaction didn't need to be so rude or unhelpful.