poor servicing (cancelling orders without communication)

I placed an order with Makro online on the 4th and I got confirmation that my order was successful. However it was divided into 4 parts and every day I would get 1 or 2 items delivered out of 20plus items that I had purchased. As if that was not already inconveniencing me, I then get an email 3 days after putting in an order and getting my first delivery saying that some of the items have been cancelled because they're out of stock. I then called their customer care line to try and figure out why was delivery confirmed if what I had bought was out of stock but the agent (Refilwe) I spoke to was not able to assist she the advised me to call the Makro Woodmead. I called the store but I did not get any assistance as I was mad to hold for 10 minutes for them to transfer me to online department.... This is very annoying because every month whenever I buy online I never get my full purchase I always get an email a day before delivering that some of the items have been cancelled because they're out of stock.