Superb central locking problem

Hi Guys

Problem with my Superb  L&K 190 DSG 2016

Each time the car slows say to approx 15 MPH the central locking clicks as if it's trying to lock again

the sound seems to be coming from the back door drivers side, the other thing I noticed is that while

the lock button within the car will lock doors it will not open them , my local Skoda dealer is ordering a new door lock unit

but I am not convinced this will fix the problem, doors lock normally when car reaches the set speed  and the

key also works ok

any ideas?