iCloud Device missing in "Find my..."

[michalm]

I have a family set up and one of my users is using several devices, one of which is not visible in Find my... It is the iPhone. Not even the users himself sees the phone there. Web, app, everywhere is the same. The phone is however reporting the location and location sharing works, so I can see the users on the map.

Any ideas how I can make the iPhone reappear there? And no, I have not tired wiping it, removing it and setting it up fresh :/