Bending rules to suit the store

In March this year I purchased a trimtek lawnmower and trimmer combo at Carnival Makro.8 months later when I was busy trimming my grass the trimmer packed. Knowing it had 24 months warranty, I called customer services that advised me it was brushes and I am cover I just have to bring the unit to the store of which I did.. then they claim they were trying to get hold of me as I need to pay R540 . I told them it’s their unit that failed so why must I be paying the damages. Then Neo from customer service advices me to go collect my trimmer as they cannot help me the motor burnt and they do not cover that under warranty.