On-line shopping but no delivery

I ordered 2 bicycles, helmets and locks on 15 January with the expectation that the items will be ready 8 days later. I am still waiting. I sent numerousmails, phoned 7times (from Germany), and even tried to cancel this order. They told me on Wednesday that they will fetch an out of stock bike from the Woodmead branch. This morning they tell me that it hasn't arrived yet. I left 2 messages on a cellphone today (number they gave me) and sent 3 mails. Why must it be so difficult to buy from Makro?