CAPITEC LOSSING ITS BALANCE

I had done a Rain Mobile payment thought its application. The transaction was approved (successful), however Capitec had decided that I don't have funds and subsequently rejected my payment and charged for it. This is a joke- I have more than sufficient funds in the account. How is this possible? Capitec is truly pushing my patients to the next level. I would like a total refund, cost and my wasting all my airtime waisted in holding on for there customer services for over 30 min.