Hello landy lovers

Im after some advice im new to the disco 2 but handy at auto electrics and machanics.
My question is the central locking doesnt work on the key. Keys light up but car doesnt unlock. All the doors unlock if i use the door lock which is abit ropey.
Is it worth replacing the receiver in the roof or not with me previously having issues with the bcu/idm resulting in hard wiring new hazards and indicators in.
Or should i just go aftermarket kit with fobs??