HomePod cant find my iphone

I've had massive problems with all my HomePods always, it couldnt even manage to stop my alarm recently. At the moment when I ask it to find my iPhone it says 'your iPhone is not available, check that it's switched on and up to date'.

Please no comments on whether the phone is on find my, whether I have the latest software or if I've tried uynistalling and reinstalling everything, because I have several times.

[Edited by Moderator]