Porblem with adding Sonoff 2CH to HA

I have used Sonoff 2CH switch to control lanterns and ceiling lights outside the house. Sonoff has HAA firmware installed. It is found as a 2-way switch natively in HomeKit. I deleted it from HomeKit and it was found in Home Assistant. Unfortunately, it is possible to add only the main switch. The seconf one is found, but when I try to add it to HA it says, it’s already added (the same name I guess). Anybody knows how to solve it?