Harassment by Vodacom

Actually minus 5 stars. I had a query going back nearly 2 years on two contracts that was never resolved and just gave up. We decided to cancel our contracts with Vodacom and go over to prepaid due to this. I was a customer for 19 years. When the call centre called me to do the upgrade, I told them I am not interested and they need to register that on their system and never to call me again. Since then I received an increase in the number of call centre calls and when I told them that they must stop calling me (yesterday they called 3 times during working hours) I received another 7 calls today. This is harassment and it is the last straw.