Hello Mikec,
1. are you using paring code 2121? (I have only used iPhones and this is the code that I have used)
2. I am sure you have tried several times but just checking.... Delete the phone and pair it again.
3. Make sure that your phone's Bluetooth is on.
4. Have you tried to connect the phone with the factory cord?
5. Ok, here is the final note - I have a 2012 Range Rover Supercharged and just upgraded my phone to an iPhone 8. I have had nothing but problems with this. Have taken it to the Dealership 3 times to fix. They tell me that the newer iPhones will not work with our generation RR's. I upgraded from an iPhone6 which worked had perfectly. iPhone 5 worked perfectly with 2005 Range Rover HSE & 2007 Range Rover Supercharged. iPhone 6 worked perfectly with 2010 & 2012. iPhone 8 connects but has very poor connectivity with a lot of static.
Hope this helps