big big problem

[graemma1]

hi all, i have a huge problem. I went to use my car last night and with it being icy outside the locks were frozen, the key jammed in the lock and the the plastic shroud snapped off. managed to remove the metal part. Collected my spare key (which always worked) and tried to start car but the immobiliser light is flashing and only allowing the car to run for 1 second. Why has this happened as there is no damage to the spare key

[chittychittybangbang]

Which plastic shroud, the one around the ignition key?