2020 JAGUAR F-PACE Steering Problems

I drove through about 12 inch water during a flash flood rain down pour. After driving about 200 feet, my steering failed. The instrument panel displayed, power steering assistance reduced. I could not turn the the steering wheel to get in the parking lot. I Google to see what the problem was and there are a lot of people complaining with the same problem. I had towed to the shop and the extended warranty I purchased said it was preexisting problem. I had just purchased the vehicle approximately 3 months prior and had never had this problem. It only messed up after running the water and that is what other owners stated. My comprehensive insurance would not cover neither. Jaquar want to charge me $6700.00 for repair, which I believe should be cover under my warranty, insurance or Jaquar itself. I contact Jaquar headquarters but having received a response.Thank you