Out of pocket due to bank error

The new bill payment feature that fnb is promoting has caused me to be out of pocket by R3550. I made a payment on Wednesday only to get an error message. However the funds have been reserved against my account but the municipality have not yet received the funds. I have now been told to dispute the transaction ( which can take up to 10 days to get a refund) in the meantime I must ensure that my lights and water gets paid.