Renault South Africa and Renault Clearwater. Absolute horrible service

Absolute horrible service experienced. My sister car has been standing for 3 weeks at Renault Clearwater with a broken engine. Till this date have we not received any call from the Branch Manager, Service Manager and the Workshop Manager. They refuse to give her a loan vehicle and everyday is a different story for the delay. They blame the customer for a internal fault that caused the engine to break.