Discovery 4 2012 Immobiliser problems

Hi guys, anybody have any information that may help? My 2012 discovery 4 was parked on the side of a busy road. A lorry went passed and set the alarm off.... the key fobs wouldn’t allow access / unlock the car. I used the manual key but still couldn’t stop the alarm. I decided to open the bonnet and this silenced the alarm. However, the car is now is some kind of shut down mode / is fully immobilised. The battery is charged and is at 12.4v. But the key fob won’t unlock and (the rear doors won’t even unlock manually from inside) any ideas?

Welcome to LandyZone

Hello and welcome
12.4v is not a good battery but best ask over in the disco section of the forum
https://www.landyzone.co.uk/forum/land-rover-discovery.8/

Welcome to the forum