Non delivery of school textbooks by Armstrong's

I ordered 4 books from Armstrong's and only received 2 of the books as they said that they were still waiting for their supplier to get them the other 2 books. I then followed up with the on the 17th February and they responded to me on the 18th February saying that they would have the books in the next week or 2. After not hearing a word from them I then contacted them again on 11th March to find out when they will deliver the textbook as I had an assignment due on the 14th March and needed the textbook to complete my assignment. They then told me that they will not be getting stock and I should go to another bookseller for assistance. I then had to be the one to ask them for a refund as they made no mention of giving me my money back. They took my banking details and I'm now waiting for a refund. This was really bad service.