order cancelled with not reason

it is the second time that I placed a order and then they just cancel it and give me a credit. last time I could not find the items again, Yesterday I received a SMS that the order is ready but when I got there only one piece was there and the piece that I needed was cancelled and credited, I did not make the minimum to get free delivery so I opted to collect but at a cost but they only credit the item value they should at least credit half the collection cost as well as only half the pieces was delivered, There is also not even a customer service link where one can complain too probably because they will get flooded with bad emails. I see the same product is still available for selection but I have to pay in for the delivery as the credit is less that the amount payable again BUT delivery is then ONLY for the 2nd September BUT THIS ITEM IS NEEDED BEFORE THEN in fact it was needed tomorrow already.