mrp mobile

I bought a cell phone on line with MRP IN 2017 and my monthly deduction was R89.00 per month. in May this year was my last payment with them. July 2019 they deducted R130.00 from my bank and when I query what was the money for I was told it was for the data and airtime they used to give me every month on a sim card that was with a 064..... number that I never used and I was told that I should have emailed them to cancel the payment in May2019 who's responsibility is it to send them a reminder and I have never paid this amount when I had the contract with them. Now that I have finished paying them they are treating me like this I'm going to reverse the money from them.