Door locks

[Omen]

Can anyone please explain 1) How the door locks work eg is there a vacuum pump, a solenoid, something else ?

2) How to remove the interior door trim to access the mechanism.

All doors will lock when necessary/required.

But F/N/S door will not unlock when either the internal button, (under the menu/nav screen etc) or the fob button is operated.
All the others unlock.

’Er indoors is getting a bit testy, thinks I don’t want her in the car . . . . . . 🤔

Thanks for any help.