Unhappy Customer

I opened an account at Mr Price last year & now I'm paying R99 for unknown product (Airtime Topup/Sim Card). I went to Mr Price & I also called their call centre to cancel it but no one helped me. I received messages 2 months back saying it was cancelled but still it appears on my monthly statement & I'm still paying for it. All in All I want to advise people to check this because according to my understanding I think Mr Price is de*****ing many innocent people and we are not aware. I've asked for help since April but no one is helping till Today.