Turn around time Avis car taken C686994

My car was in an accident on the 5th of December and i called my insurance for a car while mine was being assessed. Avis called me to pick up the car which i was given a grade a car on the 6th and was told to come back the next day for the right one. I got the right one on the 7th. Now i receive a call on the 18th that they are going to fix my car. On the 23rd they call me to tell me my car will only be fixed in January the 4th as all the shops are closed. Told them how will my car need to be fixed, they told me 14 to 15 days. I told them how will i get to work as i stay in Kempton Park and work in Auckland Park. They told me it is none of their business i only have a cover for one month and that is all they can give me after the took two weeks and changed from one shop to another during my claim. I called and spoke to Gerhad Manager that i would not loose my job over this and need my rental car extended on their cost as i still need to be my access amount of R8000.00, Miway says do this your way, but this is not even close to the my way. The car must return on the 6th and i am going back to work on the 4th. How will i get to work? must I loose my job...