Vodacom - Left a sour taste in my mouth

Since the 1st of October my number ceased to exist any more. I went into Vodacom and was told that my account was cancelled? I was not informed or warned, It had just been cancelled. Then I was told that I had an outstanding amount but they couldn't give me the exact amount. Again I was not warned that anything was outstanding.

Then I was told that because I am not the main account holder, I must get the main account holder to call in to discuss. So the main account holder phoned the number given but it tells us to put in the number that we have a query on, when adding the number it tells us that the number no longer exists? How the hell are we suppose to query this when we cannot use the number because that number was cancelled? I managed to go through to a different department and after being transferred FOUR times, I was told again that the main account holder needs to speak to them. Please explain to me how the account holder, who is in her 70's is suppose to fumble around before someone can help her? She went into a Vodacom shop in Durban (I stay in JHB and she stays in Durban), and she was told they could not help her. This is beyond pathetic. I haven't had any issues with Vodacom but since this issue, I am on the verge of switching providers.