HomeKit invitation stuck

To give some background, I have some HomeKit devices set up in my home and they work great. I've successfully been able to add the rest of my family to the home with the exception of one person.

With this person, I am able to send the invite in the usual way, and they receive it. However, the problem comes when they try to accept it; after clicking Accept, my device shows that they are now added to the home. The problem is, though, that this member of my family never gets past the accept stage - they cannot access the HomeKit setup like we can. Instead, they get stuck on this screen with the spinning wheel for a seemingly infinite amount of time:

After trying the obvious things like removing them, re-inviting them and logging out/into their iCloud account, I became frustrated and did some googling. It seems that this is (or used to be) a common issue as you can see here. The strange thing is that all the instances I could find of this problem occurred mid-2018 when I understand there were problems with that version of iOS regarding HomeKit. As a result, I made sure to check that all of this family member's devices were on the most current version of iOS (12.2) - which they were, and thus I am now stuck and unaware what else to do.

Does anyone have any idea what is causing this issue and what can be done to resolve it?

Solution 1:

I recently had the same issue and was able to resolve it with the steps I described in this answer https://apple.stackexchange.com/a/371383/10494