Unable to pair Edge 25 with Pixel 4

It seems to be impossible to pair the Edge 25 with a Pixel 4?
Both mobile app and device firmware are fully up to date.

Clean install of the mobile app, hit "add device" i immeditaly get a "device connection error" message on screen (this is before i even attempt to pair anything).

I then manually select the device from the list, but the device into pair mode (Read to Pair), hit "search for device", and it just counts down from 30 to zero then says "device not found".
interestingly, i am able to manually pair the Edge 25 to my phone manually outwith the app, but even when that is done the app still doesn't see the device.

Any ideas?