Parts missing in engine compartment

I took my car for a 45000km service at VW Barons Cumemborg on Monday. At around 14:00 I received a call saying the vehicle is finished and i can pick it up, so i did. I assumed that since the car was driving fine that everything was well. However when i checked this afternoon around 17:00, the brake fluid cap and some bolts in the engine compartment holding a filter housing was missing. So I called the dealership and they promised to call back shortly. No call back at all. I tried calling again and no answer seeing as they must have gone home. I`d like to say that this is my first time experiencing such from a VW service center but is not. I have experienced similar issues with Cape City VW. Horrible workmanship and super negligent. The total disregard for safety and standard disgusts me. I am an Electronic Technician and cannot understand how such a giant company can continuously allow such incidents to occur. Totally lost faith in this brand.