YellowData deducting months after cancelling services

<p>I cancelled my R99 data subscribtion on the 7 March 2017, To my suprise YellowData is still deduction money from my account and when I called today(28 July 2017) to find out im told that the issue will be handed over to the billing department which I should expect a call from after 10 days. Why should money still be deducted when their system states that cancelled. THIS IS TOTALY UNACCEPTABLE, I SHOULD BE REFUNDED BACK MY 4 MONTHS PAYMENT AFTER HAVING CANCELLED.</p>