HomeKit says "No accessories responding. Remote access not set up." But I did! What am I missing?

The HomeKit app on my iPhone is telling me that remote access is not set up. But I followed all the steps I was supposed to follow, according to Apple's website and several online videos. I am logged in as the same user in iCloud and my Apple TV. Both devices have OSes that are up to date.

Can anyone suggest any steps I may have been missing?