Personal details still not updated.

I have requested Cell C numerous times update my personal details as it reflects incorrectly on my monthly invoice statement. I have asked again last month via the call centre as your walk in centres are unable to assist, I was promised that it had been updated, guess what - I received my statement today and it has still not been updated. As a paying customer one expects a service provider to attend to your query and not be left to feel that they are doing you a favour. Why should a business first be given a bad review on a public platform before a customer is attended to?