Capitec duplicate charges not resolved

I was forced by Total energies to pay twice for petrol because their machine declined my purchase but capitec still took my money. Total says just walk into a branch but that didnt work. That was more than a week ago. Capitec call centre now requires me to chase after my money by driving all the way back to the garage which is far away from me just to get an authorization letter from Total to say they are not planning to take the money for themselves. Why am I responsible for Capitec and Totals error? They are only strict when it inconveniences the person whose money was taken.