Vodacom empty promises

I wrote to hello Peter complaining about about Vodacom , they responded to say they will call me of which they did , they promised to update and close the account as it’s affecting my credit score , they said it take 7 days, it’s been more than 7 days nothing has been done .I’m not owing vodacom but they don’t want to close the account and update their records that’s the account is closed . This is frustrating. They call and make empty promises and they don’t resolve them , I can’t buy anything as the Vodacom account is written that I’m owing when it’s paid off, what am I owing to them