Vodacom doesn't cancel, but upgrades instead!

My mom is a pensioner, she took a contract out for me while I was still studying. Then it went over to a sim only deal. She's been trying to cancel the contract for 6 years and change the number to prepaid, but everytime she calls to cancel, the number gets upgraded ,its very frustrating and inconsiderate of Vodacom to disregard people's wishes just to make money.

Someone needs to step up and do the right thing FFS, why must I pay for something in the end that I don't need or want and it's not even my contract.