Digital purchase of Prepaid airtime

I buy my airtime via a banking app. I happen to hv 2 SIM cards on my phone MTN airtime I never have problems receiving via my banking app. But Telkom airtime is another story. I have now bought twice airtime to the value of R300 ...R200 on the 25th of Aug and R100 on the 2nd of Sept. I am yet to receive my airtime from Telkom...fnb tells me u must phone Telkom...telkom me to phone FNB. I really don't care abt the corporate deals they do with each other...bottom line consumer doesn't care. When I buy airtime that's what I expect.