MTN WOW Bonus a *******

I currently switched from contract to prepaid. I loaded airtime several times to my phone and used it for short calls but the airtime gets finished quickly overnight. I called 173 and told them that I want to opt out of their wow bonus promotion. They told me to dial 130*501*1#. I did what they instructed me to do but i am still getting sms's telling that i received a wow bonus. I do not need this **** in my phone. Even when i buy data, the network is so poor that it takes a century to open a page. I don't even know how people from the rural areas put up with your shady service. This is a useless promotion that rips people off and i am not interested in getting it in my phone. Switch me back to my usual way of buying airtime and seeing where my airtime is going. I cannot put up with this ****. I currently have 3 contacts with them and I now regret it . Jesus Christ can somebody help me int his hell hole.