Customer must sort lack of stock out

I ordered a computer to be collected from the Rosebank store earlier today. This is a laptop that is promoted on the website. Not long after, I received a call from the Rosebank branch informing me that they do not have stock of the specific computer (Why it doesn't get sent to them from where it would get sent from if I had it delivered to my house, I still do not understand), and that I should contact the helpdesk to cancel my order. I then called the 08600 number, and was given another number, but nobody picked up the phone. I proceeded to use the online chat help on their website, who then informed me I should email if they do not pick up. After I requested Doran whether he will receive the e-mail, he rep**** quite rudely that somebody else does that. Upon him asking if he can help me with anything else, I said I'll rather take my business somewhere else. He than said if I have any problems I should complain at some email adress he gave me. In the mean time I did email to request a cancellation of my order, but after the exchange with Doran, I requested that my order not be cancelled, as I would first like this terrible customer service be taken note of.