[R12345A]

Hi, I am hoping someone will be able to help me with an issue I am having with my 2016 F26 X4. I've owned it since new and the tailgate has given me no issues at all however a couple of years ago there was a minor adjustment to stop a slight rattle from this area which was resolved during a routine service.

It's been working fine until recently where I have to press the button to open the tailgate twice and even sometimes 3 times for it to open. When I press it once, I can hear it release the tailgate however it only opens very slightly. It's only on the second or third press that it opens fully. It closes perfectly every single time. Can anyone point me in the right direction?