charged 35 per day from Opera telecom (pty) ltd

I have a R500 voluntary call limit on my phone, unaware to me Opera Telecom (pty) ltd had been charging me R35,00 per day for a service that I have never signed up to, once Vodacom soft locked my phone I went into ask them Why, this is when they told me about this ****, where you can get a pop up on your phone and even if you decline the offer of there service they still charge you, Vodacom have now stopped the subscription, but have told me there is nothing they can do to stop the payment, I find this totally out of order that they can allow a company to carry this out, if it had been my bank account the bank can pull the payment back so why cant Vodacom, if I don't get any communication from them I will be taking this further with Vodacom and Opera telecom, its a complete joke that they cant stop this company from take my hard earned cash, very ****ed off.