Zasttra is not transfer and honest to their buyers

I place an order last week Tuesday the 12th of June and on their website it said 3 to 5 working days delivery and after 4 working days I phoned them to track it and then that time they told me no it's 3 to 5 working days to prepare then another 7 to 10 working days to deliver and after 7 working days , Tuesday the 17th I phoned them again just to see if preparing is done and shipping has commenced, I was then told NO actually they don't have it in stock this is after 7 days of me asking them where is my stuff and why it took 7 days for them to know they don't have stock. Then when I ask for my refund, I am now told that it's going to take 7 to 10 working days to get my money back on top of 7 working days I have already waited.