Following the rear window washer pipe becoming detached ( now fixed by dealer) and soaking the lock the opening of the tailgate is not now detected and the automatic locking comes into play if the tailgate is opened but no other doors are. Is there an easy way of fixing this problem?

Hello and Welcome to Briskoda

No easy fix, this has sprung up a few times before. You will most likely need to visit your dealer for a new switch and/or check the connections.

Make sure you keep those keys in your pocket when rummaging around in the boot.

I've had this exact same problem and they replaced a part - the sensor I think, however it doesn't appear to have fixed it so it has to go back again. Mine was also following a leak from the rear washer.