Called MTN up, apparently the first person I had spoken to had logged it under "Itemised Billing complaint" instead of "Billing error", thus the ticket just sits there permanently open with no one touching it. Apparently no one at MTN who deals with "Itemised Billing" complaints is empowered enough to reroute an open ticket to the right department, they'd rather just leave it open till you call again.
Now I call them up again on the 8th to nanny them along and make sure they haven't gotten anything wrong again.
Diablous: I agree that it can be a lot harder to tell exactly how much data you've used with MTN Actives site compared to V4M, but when their main billing system is as broken as this you can see why they don't spend time adding "fancy" features like being able to properly limit OOB usage.
