Unhappy Treatment

I took my car for warranty repairs at Hyundai Plumstead on 14 May 2024. Dropped the car as per usual at 7am. No inspection was done and because i trust Hyunday Plumstead for a long time as i have been there client for many years without a problem. Vehicle was taken to another vendor for repairs. When vehicle was returned, i assumed everything was in order and was very satisfied with the repairs that was done. A few days later, i noticed that i could not use my Maps. I then checked why only to find that the SD card that supports maps location was removed. I immediately drove to Hyundai and advised them. The person that booked my vehicle in was very helpful on the day and advised me that he will look into the matter. The following day, he informed me that his manager told him that they cannot be held responsible as they do not know whether the SD card was in the vehicle when they took it. I advised them if they can at least find a way to check when the SD card stopped registering. The answer was they do not have such facilities to check. I advised them how important that card is to me as i use it daily in my type of work. I received no help and all they told me is that they are not responsible. I find this very disturbing and also knowing that i am a client of them for years and i have never had any such problems with them whether i take the car in for service or something else. Since 2018, i have been servicing my car with them and nothing has gone missing. I do feel like Hyundai should take responsibility for that and replace my SD card. When i handed the vehicle in, the SD card was in the car. I do not have reasons to remove it. Please help