Vodacom
No Feedback on Line fault

On the 17th of December, I received a WhatsApp message from a friend, when he calls me, he gets a message that says the Number does not exist.
I was able to make calls, and send messages, but couldn't receive any.
After spending more than an hour at Vodacom Centurion the queries was logged at Vodacom's technical department.
Next morning the phone worked again.
The same thing happened in June 2012. Up to now. no one could tell me why this happened. I asked several times when talking to call centres that I want to know why this happened.

I expect an answer from Vodacom and some kind of compensation for service that I did not receive, and for the inconvenience.