Freelander 2 (LR2) Doors lock but wont unlock..???

Hi All, sorry for posting in the wrong area.
We have a 2013 Freelander 2 td4 HSE, about 45,000 on the clock. Its been parked up for a while due to the bug, and the battery warning has come up a few times. Wife reported the doors all locked OK when she went into work, but wouldn't unlock via the keyfob. She could open the windows via the fob and reach inside, the doors unlocked from the handle, and via the buttons on the dash. We can hear the solenoids working, and the alarm chirps.
I took it for a nice run on the M3 today and the battery is fully charged, but again I can lock it with the fob, but it wont unlock. The rear hatch DOES unlock from the keyfob.
Further diagnosis, I see the black lock knobs on the door handles move freely on the passenger doors when I blip the fob, but the drivers side knob feels crunchy, and is reluctant to move. It also seems to lock / unlock all the others, there must be a master switch in there, so if the drivers door wont function, neither do the others. Good design there Mr Landy.
I'm guessing its old age, I gave it a squirt of dry silicone lube, I see on the interweb many folk report similar problems, suggestions to swap the battery, but this feels mechanical to me. I guess the next step is to rip off the driver side trim and have a poke. Any thoughts?

As far as I'm aware, all doors are powered by the CJB, not just the drivers door, which then powers the rest.

Try a hard reset first, and see if the problem clears after that.

Thanks, not sure what a CJB is, but the lube seems to have done the trick. It opened up first dab on the keyfob,

The buttons on the dash and the fob seem to unlock everything, but the internal black lock levers above the shiny handles don't - only the driver's door does that. I found a Utub video showing how to remove the door "card" but I didn't need to go that far.

Here it is for anyone else encountering a problem: ( Obviously google will want your inside leg measurement and the hand of your youngest in marriage.) https://www.bing.com/videos/search?...BFAA1E2B29920214C248BFAA1E2B2992&&FORM=VDRVSR