No call back

Zero stars if that was possible. I am trying to get hold of the call centre concerning my line. I have been into the store at Century city and asked that a call be logged. I was then told that the call centre would return my call within 15 minutes, which never happened. Today I went into the Tygervalley store where I encountered a very unfriendly store assistant, Anastasia. Once again 3 calls have been logged with no call back from the call centre. This is highly frustrating and terrible customer service.