Cancelled contract and repeated refunds and deductions from vodacom

In the middle of January I phoned to cancel my account. The call center assured me that the end of January would be my last payment. February they still deducted money. I immediately phoned them and after holding for hours they responded that the money would be returned to me within 5 working days. It had been 3 weeks and I had not been refunded. So I wrote a hello peter and disputed the charge on fnb.

Vodacom contacted me and said they will refund the money with 14 days. I received the payment.

Today vodacom has deducted twice the usual amount for my cancelled contract back in January after they refunded me. This is ridiculous. How long is this going to take to get resolved? Why should I wait several weeks before I get my own money back for services I DO NOT USE anymore.