Unable to assign a device to a person

What I am trying to do: I would like my presence of home/ not home to be determined by the location of my keys. My keys are a TILE device and the TILE add-on is added to HA and appears to works as I see the keys come and go in history. (I am trying to do this configuration using the GUI but no issue if coding is required, been a coder since the 70’s). The keys device are always with when I leave the house, hence why they are chosen.

What I think I have to do based on docs: I go into settings, select people and then select the person (me) I want to track if they are at home. I then select the pulldown from the “Pick devices to track” pulldown menu in my page. This is the page with a picture, “allow person to login”, “Administrator” toggles. I see a list of devices and select my keys, ‘device_tracker.n_keys’. However after clicking on the device I’m back to the ‘Pick devices to track’ however they do not show underneath. This applies if I select any of the tracker devices. This is the problem, I can’t seem to associate the device with me.

Home Assistant Core 2022.5.5
Home Assistant Supervisor 2022.05.3
Home Assistant OS 8.1
Kernel version 5.15.32-v8
Agent version 1.2.1
Path to configuration.yaml: /config

The install was a straight forward hassio onto a memory card and it runs on Raspberry Pi 3+. I just went with something simple to get used to HA.
I have tried this under Windows 10/Chrome, Android/Chrome and iOS/Chrome.

Things I have checked: Any relevant docs on people and device tracking, questions here, general Google search for other sources. AFAIK it should just work, which is the confusing bit. I see all the other problems they have but don’t appear as simple as not being able to just assign a device.
When I look n the history I can see the keys coming and going.
I have probably spent about 4 hours over 3 days trying to get this working.
I have run the app on my Android phone and then that device added automatically, even though the phone had already been added. However this just showed me as home all the time, even when I left home with the phone. (Track always is enabled within Android, its a Pixel 6)
When I go into developer and look up the keys device (device_tracker.n_keys) I see this for them (gps actual location replaced with x’s however it is correct :
source_type: gps
latitude: -34.xxxxxx
longitude: 138.xxxxx
gps_accuracy: 46
altitude: 5.9
is_lost: false
last_lost_timestamp: ‘1969-12-31T23:59:59.999000’
ring_state: STOPPED
voip_state: OFFLINE
icon: mdi:view-grid
friendly_name: N Keys

The state currently shows ‘home’ in the history time graph which is correct. My location is shown as unknown because there is no device with location attached to me, I believe.