Disappearing airtime and bundles

I have been experiencing this problem ever since MTN officials were on strike and I thought this problem will go away. Last night 06 August 2015 my airtime disappeared again and I bought R30 airtime and R35 bundles on 07 August 2015 at 9 o 'clock and it also disappeared. I then bought R60 airtime again at 10:39 which also disappeared. I then called the service provider at this number 173, Since am on contract I was transferred to the contract department I was holding until I was cut off. This service is unacceptable and it looks like MTN is not ready to remedy this situation.