Poor customer service and dishonest communication

On Saturday 4 May I made an online purchase. On Sunday 5 May I received an email stating that the item was out of stock and that my refund "was already on it's way back" to me. Since then I've received at least 12 emails stating the same thing. By Monday 20 May I had still not got my money back. That same morning I called the online purchase number because I could find the customer care line. I spoke with someone named Monde who said he would follow up on the matter and give me feedback that same day. This did not happen. On Tuesday I emailed every Leroy Merlin address I could find to see what's happening. It turns out that my refund was only requested internally on Tuesday 21 May. That's 12 working days since they first told me the refund was "on it's way back" to me. I'm not willing to wait another 2 weeks for my money. I just want my money back and I will never shop at this place again. It's impossible to get any assistance,