Poor customer service

JMC Centurion has the most poorest customer service ever. We took our car there for the gearbox to be fixed. The gearbox is covered by the warranty and we even confirmed with the warranty holders on a call with the owner of the brunch at jmc Centurion with the warranty company on the call . JMC just fixed the car with out following the warranty instructions on the documents sent buy the warranty company. The calm was rejected and now we have to pay R20000 out of our pockets. They have no care for customer service at all.