Truworths selling stuff they dont have in stock

I am really frustrated and annoyed by truworths online sale. I have had over 10 orders cancelled. I order clothes which clearly show availability when I pay then the next morning I get a text message saying order cancelled. This has happened over 10 times in the last 2 weeks and honestly I am getting irritated. What makes it worse the refund process takes so long I cant even track my funds because there are too many cancellations. 2 days ago I ordered a denim trench coat size 36 it was available at that time because yes my process went through 15 Aug I get a text message my order has been cancelled. Immediately I order size 38 and its available again. 16 August I get another text order cancelled. No no no no truworths this is unacceptable why does it even happen only with your store. Now I am searching for availability in store I can see mall of tembisa and cresta has a size 38. So I am thinking I drive there again only to be told no stock. I am so so so annoyed. If you dont have stock please stop selling stuff you dont have. I have already paid twice the amount just to get a sorry for the inconvenience text. I have tried communicating about this on facebook since yesterday and no response. Please fix this ....this is unacceptable. I need my order delivered.