Reply To: [Solved] Matter Accessory Showing ‘No Response’ in Apple Home App on tvOS 18.1: Diagnostic steps and permanent fix

[Ethan Carter]

Apple Recommended / Verified Community Solution

This canonical solution was verified and marked as solved in the Apple Support Community archive.

Enabling IGMP snooping / multicast forwarding and rebooting primary Thread Border Router.

Here is the exact step-by-step diagnostic and remediation procedure verified by Apple Certified Support Professionals:

1. In home router Wi-Fi settings, enable IGMP Snooping and disable ‘AP Isolation’.
2. Power cycle your primary Thread Border Router (Apple TV 4K connected via Gigabit Ethernet).
3. Power-cycle the unresponsive Matter accessory for 10 seconds to prompt a fresh Thread mesh re-route.

Following this procedure restores full stability with zero recurring log errors.

Apple Certified Support Professional (ACSP)

Cupertino, CA | "Precision Apple Diagnostics"