Waiting for airtime up to 72 hours

I purchased airtime on Sunday evening 9 August 2015, as well as my mother purchased airtime for my phone. It is now Wednesday 12 August 2015 and i am still awaiting the airtime to be loaded on to my phone number. I have called the call centre various times on Monday and Tuesday, and get the same story, they are working on it. <br> The money have gone off of my bank account. This is unacceptable.