Vodacom *****ing from me

I called vodacom the beginning of March to find out about a certain R3 that's goes off my account every second day. I was told I Opted in for a data refill in 2019 which was all new to me. I was informed on how to cancel "opt out", which I did but the services kept taking money. I started making it my business to opt out from the service every single day, but the money still goes off. I don't even use data but wifi, how am I getting refills for something I don't use. Each time I opt out, the message says "I will be notified once the services have been deactivated", which never happens. I want my airtime refunded because this is ridiculous!