Bmw supertech newcastle unprofessional and unreliable

My car went for repairs on the 6th of july but have been with Bmw Supertech Newcastle for almost a month and a half.All along Im without a car in this pandemic period.Last week Monday I was told the car will be delivered to me on Thursday but when I called on that very Thursday I was told that the part that was suppose to be replaces is not available at Bmw South Africa.It will be ordered overseas and will take more weeks or 3 weeks even.This was so confusing and more frustrating because all along they have been saying the part will arrive on Tuesday and they will fix the car.I have been without a car since the 6th of July and it is their mistake that my car is not fixed.David have not been communicating but instead when I do call he doesn't pick my calls and never even returns my calls.Sunaina the manager promised to fix this and atleast give me a courtesy car but she is also not picking my calls now.I have resorted to writing emails to which she keeps apologizing and promises to give me a courtesy car which has never happened.Im so angry and very frustrated even worse this is a time my family needs me the most especially to bring medication to my covid19 positive family members.I urgently need help.