No Refund

MTN online called me to upgrade my lines, did quite a few. No mention of migration fee per line nor that I will be billed pro rata and because they called me at the start of my billing cycle, I was charged for both packages, full price. I was called after laying a complaint when I saw my bill which was double the usual and was told that I will be refunded in 7days. It's been more than 3 weeks and still nothing.