Handoff not working with homepod mini

I have an iPhone 12 Pro Max, two homepod mini's, and a full-size homepod.

All of these devices have the latest software (iOS 14.5, and homepod OS 14.5).

Handoff works perfectly with the full-size homepod and one of my homepod minis, but refuses to work with the other homepod mini. Have tried resetting the homepod mini and my phone, and also other solutions offered in other threads, such as checking handoff for the homepod is turned on, and also the weird solution for turning on motion & fitness settings (which were already turned on).

Seems like this is an issue for quite a few people, and I've seen nothing in any of the threads that provides a consistent solution to this. Anyone?