Reset central locking? Security and key not working..

[Persian]

A 2nd issue I've been having.

My key, no longer works. It only turns the car on and off.

I can no longer turn the door to lock or unlock the car.

I've been parking it unlocked.

The trunk opens at times.

The interior lights no longer turn on when you enter the car.

The car alarm flashing light does not flash.

Key in center console does not work. Hazard light key DOES work.

I assume this is something to do with the central locking. My brother had someone tell him its a battery problem? The car has 248100 km on the original battery. But I hear BMW batteries are almost never the issue in electrical problems?

Any advice is appreciated.