Incorrect Billing on my account

Due to affordability, i cancelled my membership for both my kids and myself. A month or 2 later, i was called and advised that I would be paying R150 for my membership because of vitality. I then only activated myself. An amount of R450 was debited and rejected on my end and i address it, 2nd month an additional R450 was debited again. I asked that someone rectifies this instead of billing me incorrectly for months. Can someone urgently assist me, as my bill keeps growing and it is not my fault