Homekit multi user geofencing

I'm not able to make homekit automation work with my wife.

I mean, I've set up an automation like: "when the last person (between my wife and I) leave the home turn off the lights, but it doesn't work. If if take her out of the automation it works fine (just with me).

I've read a lot of threads but none is clear on how (and if) to solve the issue.

We are both on the latest iOs (11.5.2), same as the AppleTV.

I've tried a lot of things but without success.

This thread (Homekit multi user geofencing) is very interesting, but it seems to be closed (I wasn't able to reply), the last guy in the thread said he got it working but it didn't work for me.

Are there any other ideas to get it to work?