Vodacom airtime promotion issues

[CathJ]

My mom's having some issues with vodacom's airtime promotions, and she's struggling to get a reply from customer care.

1) She recharged during the "recharge and get double your airtime" promotion, but didn't get double the airtime. Does she need to do something specific to claim it? I figured it would be automatic, but it doesn't seem to be - at least, there are lots of people complaining on facebook that they haven't got their airtime. There are no instructions on how to claim it.
2) She gets sms's every day since 3 Feb-ish relating to multiple promotions - double your airtime, 80% extra airtime and others - it makes no sense that all these promotions are running at the same time, if they're automatic.
3) She gets multiple promotional sms's every day. At something past 4 in the morning! I know it's cheaper for vodacom to send out bulk sms's at that time of the day, but not everyone wants to be disturbed for non-essential texts. Is there any way to unsubscribe?

Any idea who to contact for this? Customer care just sends her round in circles.