Telkom airtime disappearing

I bought airtime at telkom over the weekend. I noticed that the airtime disappears after a few minutes of loading. The sad part is they don't answer their calls, no replies on messages , WhatsApp's nothing. Its frustrating cause you can not make calls during an emergency. Their service is utterly disgusting and I want to cancel my contract immediately. People complaing about the same thing on Facebook. Telkom should close business.