Poor customer service

On the 30th March 2015 I took my car for a service at the Hyundai Service center - Cresta branch. I had informed the consultant Shanel who assisted me in booking my car that i would need a service book as i could not locate my one and was informed of the charge, to which i agreed. I had called the service centre twice on this day to find out if my car was ready only to be told that Shanel was busy so eventually at 17:30 i made arrangements with a colleague to take me to the service centre only to be told by Shanel that she had tried calling me (I did not have any calls on my mobile). Shanel then informed me that she was having a problem with the invoice and she had forgotten about the service book but could she send them the next day or so with the driver. To date i have not been given the documents. when i called Shanel in April she had informed me that she was stioll busy and had not fogotten about me. Last week thursday the 14th of May, i called teh service centre and was todl by the receptionist that the manager would call me back. It is now 3 days later if you include the weekend and stil i have not heard any news. This is really pathetic as i have always taken my car there