I'm on contract phone but getting no airtym

I'm a having a cellphone contract with MTN but never received airtime nor data bundles. My account is up to date. I went to the branch to inquire, relevant department was contacted to help me sort out the matter and received advice on what to do in order for my account to be reconnected since I'm paying monthly but my Sim card is on prepaid. I paid R1078 end of August which i was told it will help get my number reconnected, then few minutes after i received a message to say my number will be reconnected within 24 hours but till now my number still on prepaid however i went and pay end of September as well. I've been going to Highveld mall branch every weekend and it looks like i won't get help since when i was there previously i was told there is no need to come back there anymore since i could just request the inquiry reference number and call the service providers by myself. I tried to explain that since I'm on prepaid i wont be able to dial 808 to reach them, because with prepaid number i can only call 173 not 808 number. Please help me sort out the problem, my account with MTN is well paid and I've been using their contracts since 2009, this just started this year in May.