Ridiculous service and charges

I took a double deal contract with vodacom. My installation was R499 monthly when I took up the contract, but they've been debiting R623 instead of the agreed amount. I called to cancel the data and airtime contract and remain with the headsets contract cos I'm not even using the data and airtime and I was told I need to pay +- R8500 for cancelation of the data and airtime i won't even be using. And I was advised to migrate instead to a lower plan. I called today for a migration and I was told I need to pay R2415 fee for migration. I've never come across such a useless service provider. This is ridiculous and ******* at it's best. I regret everyday for taking out a contract with vodacom. I'm so frustrated.