Blacklisted My phone incorrectly

So I have been using my Galaxy Note 3 and one day out of the blue it stopped working I tried everything, I went to vodacom and they said the phone has been blacklisted and I should phone the call centre. I phone the call centre they pick up the phone has been blacklisted by them because my account has not been paid, I have never missed any payment. They transfer me to the accounts department and they confirm my account has NEVER missed any payment I spent between R3500 to R5000 a month at Vodacom, they transfer me back I explain that they can speak to the accounts department they do that and see it's there mistake, but in my work I do not always have the time to go to a vodacom shop, so seeing they blacklisted it, they might as well do it remotely again, as it's there mistake, now they can't do that, so I want my phone to be un blacklisted because you made a mistake I must make plans to get to a shop, it does not work like that if this is not resolved by the end of next week I will take legal action against Vodacom