Inefficient staff/lack of training

I have a woolworths black card and have been having numerous problems at various retailers whenever they try to swipe my card. Have contacted woolworths black card on over occassions but they have a standard response that they did not receive any failed transacstion. Staff refuse to understand that if the card is not recognised that there will be no declined transactions. They have poor training. Very inconvenient. I hold up the queue wherever I try to use the card including toll roads. Staff response is that the merchant must call the contact centre. Imagine that at a toll road. Pathetic response from Woolworths black card division.