Router A – main, also it is DHCP server. All devices are seen on this router, even though they connects to B or C. While B and C works as repeaters covering wifi zone where router A isnt reaching. Till OpenGarage i havent noticed any weak connection spots in my house. But Somehow OG was connecting to router A which wasnt covering that area well. So i saw OG in connected devices list, it has IP, but ping wasnt reaching it. I solved the problem with turn off 2,4Ghz network on router A. Now OG always connects to routers B wifi, which is strong at that spot. No problems anymore with connection.