Failing Sending Credentials to network Matter/Thread- Apple Home

A couple weeks ago, I changed my Apple account password due to a possible breach attempt. Since then, I've been dealing with various issues in Apple Home, and I've managed to get everything stabilized again—except for about 7 Nanoleaf Matter over Thread bulbs.

These bulbs have been rock solid for over a year, but now they can't find the Thread network. When they do connect, they fail to send credentials to the network and default to Bluetooth instead.

What I've tried:

  • Resetting through the Nanoleaf app
  • Resetting directly in Apple Home
  • Removing and re-adding devices
  • Nuclear option: deleted the HomeKit bridge
  • Deleted the entire Home in Apple Home and started fresh

Nothing has worked—still having the same issues.

Has anyone experienced this after changing their Apple account password? Any ideas or suggestions would be greatly appreciated!