u/DJ-JupiterOne

I have a new Sonoff AirGuard CO2 sensor (SAWF-08P), which uses Matter over Wifi. But when I try to add this Matter device using the iOS companion app, I get this message which seems to be for Matter over Thread.

Failed to save thread network credential error: Thread network credentials does not match with any of the active thread networks around.

Why would I be getting this from a Matter over Wifi device and what do I do to get past this? I've already used the eWeLink app to add the device to my 2.4 GHz IoT network.

I also have other Matter over Thread devices on the same IoT network and they are working fine. This is my first Matter over Wifi device.