Unauthorised debits

I registered for UberOne a few months ago a d then cancelled it when the subscription was due to end. To my suprise, I am still being debited R50 each month and the amount has added up to R400 of debited while I have cancelled the service. Sad part is that I am not getting any assistance from them even if I have provided proof that they have been taking my money. They only tell me that my UberOne is cancelled but never check or even refund me my money. I am so disappointed in their service. I have contacted them several times with o assistance. I want my money back.