I'm well above my pay-grade here, so this is just a possible musing...

?

Did you upgrade to some of the most recent FW (I'm assuming this is a CP4)??

There's some issues with HomeKit, DSC, etc. that these newer FWs break related I think to certificate management.

I don't use these interfaces but I'm sure if I updated my CP4's it would break something that they haven't identified, and maybe this is your issue...

I've been staying on the "cp4_2.8003.00056.01.puf", as it seems to be *reasonably* stable...and you know what 'reasonably' means...:)

?

Just throwing this out as a possibility...