card cancelled

I ordered an extended petrol card, when I went to collect I was issued with the exact same card I had so I didn't sign for it and ordered another one. I then went on holiday and used my original card to fill up and it was DECLINED!!!!! When I contacted the Customer Care they said it is policy to deactivate cards when a new one is ordered...how can that be?????? I hadn't received the new card yet and they blocked the card I had...what kind of service is this...??????.Sorry Nedbank, after 30 years of being your client, I feel it's time I changed...you don't give a good service anymore, unreliable!