Telkom/Google Play Music

All I want is to use the facility quoted below. 2hrs speaking to Telkom and half of the reps AREN'T even AWARE of what I'm speaking about. I was transferred from billing, to landline to cellphone to technical depts and nobody could help. The quote is as follows " Google Play Store Billing offers Telkom mobile customers an alternative to credit card billing when paying for apps and games, and eBooks and online magazines. Google Play Store Billing will let customers charge purchases from the Google Play Store using their Android device to their airtime or Telkom bill." After I apply all the settings and attempt a purchase I get a message "payment unsuccessful" Now they blame is put on GGPLAY, which is impossible because I could make the same purchase with Credit/Debit card. Can someone with KNOWLEDGE about this issue please assist....