Shocking service from Leroy Merlin

I purchased an aircon online on 30 November 2019. Delivery was said to be within 2-3 business days. After a week I was phoned to say that there is no stock. After about 10 days I was offered an alternative at a higher price which I refused. I asked for my money back. It has now been 19 days and I simply get no response from anyone. I am told a refund will take 2 weeks but the "paperwork" is outstanding. The service is pathetic. How can you advertise an item that is out of stock. How can a refund take 2 weeks? Let this be a lesson to all. Avoid online purchases from Leroy Merlin!