Telkom Selling what they don't and not able to deliver on their promise (Bad Service)

I made an order through Telkom online for a device over two weeks ago. I spent the two weeks waiting for that order and as the time was progressing i started thinking they have forgotten about me and i started making means to talk to them. Finally when i got them over the phone they told me that the order was canceled due to that they were out of stock. That is good and all but why did they not tell me or even update their catalog online cause they are still selling what they don't have. I am really disappointed on how telkom has dealt with my order. to top it all the agent i have talked too to voice out my issue has hang-up the phone on me.