Telkom takes my money for airtime but says I have no airtime when making calls

Using a prepaid sim account. I load airtime and when I try to call a number it says I don't have enough airtime . This is an ongoing issue. I truly hate the fact that I trusted telkom to provide me with professional service. I just had an emergency and I couldn't get help due to this issue. I will never recommend this unprofessional brand called Telkom to anyone.