Hyundai poor quality

I seem.to be having issues with Hyundai Umhlanga once again, I purchased a Hyundai Tuscon Nsport from them recently, the vehicle is less than 3 months old & comes with a 7 year warranty. Whilst driving a plastic (thin bubble wrap) got stuck underneath the vehicle and damaged a sensor, in order for this to be sorted out they asking us to pay 3000+ , I dont think its fair especially when we have a warranty on the vehicle, its definitely not negligence on my path as im sure they dont expect me to avoid a plastic on the road and swerve onto another vehicle. The sensor should have a cover if its so fragile. Spoke to the dp today and she refuses to sort out as it doesn't fall under warranty. So the question I asked was if I pay the money to get it sorted and I drive out of here and another plastic on the road gets caught on it do we have to pay for it again and she responded yes. Theres no logic in this. Please assist me further my contact number is ********** 073 and my name is Charleen. Thanks in advance.