I fixed the problem on mine. When you press the boot release on the handle it operates the solenoid to release the catch. There is no further motor action, there is a large spring which actually releases the lock. On mine this had got stiff so a spray of WD40 freed things up and now it operates smoothly every time. Spray the WD40 in and manually close the lock over with your finger or a screwdriver, then release it using the button on the handle. Do this a few times to work the WD40 in and rinse out any gunge that is making it stick. There was no magic trick to actually get the door open when it was stuck, I just repeatedly operated the lock while pushing the tailgate shut to try and take pressure off the lock, eventually it released. There was no way to remove the trim inside to operate the lock from within, so it just takes patience. Once you manage to get it open get the WD40 in there, don't shut the boot!