Unable to pay for account at outlets in Durban

I have been trying to pay for my account at the Vodacom outlets at Musgrave and Durban CBD with no success. I have been told that if I want to pay for my account I must go to standard bank or the Vodacom walk in center at Gateway or The Pavillion mall. I fail to understand the reason why all outlets don't accept payments. It is ridiculous as payment can be made at outlets when in Johannesburg. This concept doesn't make sense and needs to be rectified.