immobilised disco 2, no EKA

Hi I tried to start my disco 2 earlier this week but when i turn the key in ignition the immoblisier light which does flash normally stayed solid and the engine does not start (hazards didn't flash and alarm didn't go off). I don't normally lock the car but when I pressed the buttons on the key fob nothing happened so I changed the battery in the key fob but still nothing happens other than the red light flashing on the fob when i click a button. the only thing that had been done to the car recently was a few days before the inner drivers door panel was removed to try and fix the inner handle that wasn't opening the door properly. however the car does leak and it has been wet recently. Any ideas of what might be the cause or how to fix? i don't currently have the EKA code (old car but trying to contact land rover to assist there) but the key does not turn in the drivers door handle so I'm not sure how I would put in the code if I did have it

Hi, when you say the car doesn't start, does it crank but not start? If it doesn't crank then it's immobilised and the EKA is the only way to get round it if your key fob doesn't disarm it. Can you get hold of another roof receiver to rule that out?
Griff