Central locking/immobiliser

hi all. I’ve just picked up another 300tdi disco from my cousin. He had been running around in it problem free for a year or so,I collected it today, drove it onto my trailer as no mot with no problem,got home and the key fobs wouldn’t work so immobiliser wouldn’t deactivate. I’ve replaced the batteries in both fobs and it’s made no difference. Any ideas anyone? Thanks all

A lot of people seem to bypass it by the looks of things

https://www.landyzone.co.uk/land-rover/alarm-system.55949/

Cheers for that. Im.trying to suss out what's gone wrong with it .It was fine when I put it on the trailer but when I got home it wouldn't work