Vodacom problems

Good evening My parents are 87 and 86. My mom has dementia and hasn't used a phone now for at least 8 months. She us totally bedridden. Without consent Vodacom reinstated the contract in October. They had 2 Vodacom cell phone contracts. My dad pays both. We have been to Vodacom shops, phoned the cancelation department. They promise we will receive an email with their findings. They promise to look into it but say we must pay a cancelation fee but it was them who did it without consent. What recourse do we have? Would love some help Grgs Kingsley Stone