YEELIGHT GUANGCAN YLXD50YL – 'poor connection' makes it unusable

Got the light for about a week. It looks nice, is bright enough, but… it’s almost useless in smart home. The reaction time is ridiculously high – sometimes it takes about a minute to react to control event.
I’ve tried MiHome, Yeelight official app and HomeKit app (btw, the support there is partial: you can’t control ambient light or turn on ‘moon mode’) – but no use: sometimes it reacts instantly, sometimes after 10-15 seconds, sometimes half of minute and sometimes it doesn’t react at all just complaining about ‘poor connection’. I wonder how 250Mbits channel can be a ‘poor connection’. The router is just in 4 meters away from the light.

It’s my first Yeelight product and I’m wondering if all are like that. It’s totally unusable as a ‘smart device’ and comes out it’s a waste of money.

Does anybody have similar problems?