Smart account transactions in question

I was recruited to join gold smart cheque account. Was looking at switching from my bank even to re-direct my salary into. I was informed that by using smart cheque account I wouldn't' be paying for purchases transactions and swiping blah blah as it is fixed rate charge and that I will enjoy such service. cool that was a done deal, I was convinced to take. On the 25th February this year, I requested a friend to assist me with R200,00 as icouldn't't get to work, my petrol tank was empty which he did made a deposit with confirmation sms. I drove into a garage nearby to fill up R120,00 fuel. I was shocked and thought it was a joke when the petrol attendant rep**** \ the card is declined. It was so embarrassing! I had to leave my cellphone for holding while I rushed to Campus square branch to only learn and presented with a statement that said the account was overdrawn. I got worried since I was paying the fixed rate as said. May be I have a little knowledge with the banking functions and trust that I wouldn't be disappointed. Is it a reliable transaction to do? I was rescued by a work colleague to pay the bill. I requested the manager to call and clarify till now none!"