Warranty that is not fulfilled

I had my 1 year old car booked in at your Roodepoort branch on Ontdekkers for a battery check in the beginning of the week and at the end of the week my car is still there. I have phoned in multiple times and they promise to phone back but never do. What type of service is this? How long does it take to check a battery? I will never buy a Hyundai again.