:welcome2: Welcome to the asylum. Please put your location in your profile, it could be handy if you need a dig out from local members.
Regarding your problem, it would appear that someone has disconnected the antenna wire to the keyfob receiver (Blue single wire) located by the rear side window, drivers side. It can be accessed after removing the narrow trim which the parcel shelf locates. Chances are the car battery was being drained because the main ecu was being woken up by spurious radio signals. Loads of informatio on the forum..do a search.
New receiver required to stop the problem, cost around £170