I have iPhone 6s and a 2017 Range Rover. Blue tooth was fine with 10.3 phone and phone book worked well with Range Rover phone system via bluetooth. When 11.0 went in I lost connection between phone and auto. Siri will not work on Iphone wit blue to

How can I reestablish bluetooth connection between iPhone 6s using 11.2.1 and my 2017 range rover audio system.

I cannot use Siri when connected with blue tooth to my vehicle. The vehicle does not communicate with my phone, I cannot download my contacts to the vehicle screen, and I cannot dial a call using my vehicle screen. I am correctly connected and paired, but the phone doesnt communicate with the car. Before ios 11. everything worked perfectly.

I have reset the iphone to factory settings, reset both vehicle and phone bluetooth. Paired and unpaired several times, reset network settings on iPhone, checked with the Range Rover dealer. So far there is no communication between iPhone and range Rover. I have tried other peoples phones up to X, and none can connect.

Help