When you utilize Apple's HomeKit platform to run your smart home, the Apple Home app serves as a conductor, allowing you to orchestrate various devices such as lights, sensors, locks, cameras, and more. To ensure everything functions harmoniously, it's important to clean up and remove unnecessary, old, and unresponsive HomeKit accessories over time.

To remove HomeKit accessories in the Apple Home app, follow these steps:

1. Tap the three-dot circle icon located at the top right corner.
2. Select the section that displays accessories with "No response" status.
3. On the next screen, long-press the gray box of the HomeKit device you wish to remove.
4. When the settings screen for the device appears, press "Remove Accessory" at the bottom.
5. Confirm the deletion by tapping the red "Delete" button.

It's worth noting that if you need to remove a device linked indirectly to Apple Home through a bridge or hub, you would follow these steps:

1. Tap the three-dot circle icon at the top right corner.
2. Choose "Home settings".
3. Tap "Home Hubs and Bridges".
4. Select the desired bridge or hub you want to remove.
5. Choose "Remove Bridge from Home".
6. Confirm the deletion by tapping the red "Delete" icon.

In the event that you encounter HomeKit accessories that are not responding, you can try the following steps:

1. Make sure Bluetooth is enabled in the Settings app on your iPhone, iPad, or in the System Settings on your Mac.
2. Restart accessories showing signs of unresponsiveness.
3. Consider removing and reinserting the batteries of the accessory.
4. Check the manufacturer's app for firmware updates that may be required for accessories that aren't responding in the Home app.
5. Perform a reboot on third-party bridges (e.g., Hue, Aqara) and all HomeKit hubs (including HomePod, HomePod Mini, and Apple TV) by unplugging them for 10-20 seconds and then plugging them back into a power source.