Renew it Randburg had terrible after care service and clearly very comfortable with inconvenience customers!!!

Shockingly bad customer service from Renew It Ranburg. Took my car in mid August for repairs and end of September I received it and it was working. On the 17th of November my car gave me a "power steering malfunction" message. I called them.immediately and they refused to assist saying I should drive the car to them. I couldn't so I called mercedes and the collected the car. After diagnosis Mercedes discovered that the same issue that was repaired is what is causing the breakdown. They made contact with renew it randburg and all that is required is an authorization of the steering box from the 22nd of November from them. The whole week... we have been waiting and following up on a simple approval via email. Holding up my loan vehicle while I use alternative transport and am inconvenienced by a simple email. Surely... something so simple cannot put one person at such disadvantage when all that is required is a simple email post alignment between renew it randburg and the dealership. Now I ask... how long does it take to send an authorisation email??? To service the customer who has collected a qorking vehicle and is now left in the lurch by bad service and delivery??? Send the email to Mercedes Bryanston, please!! I need a car as I am unfairly inconvenienced by your bad processes.