Hi!
When I try to start my Mi TV 4a from Google Home app through voice command (Tv & Smartphone on same wifi network), it appears a remote control like screen, with only a central turn on/off button. I press it but I receive an error message (a problem occurred) and the TV won't turn on.
PS When the TV is on and I try to turn off it with voice command it works flawless.
PS No energy saving options are present in the TV settings
Try to ping your tv ip when it os off, if it fails is because the tv is in a deep sleep state and disconnected from your lan/wifi, so it can't be reachable. If so you have to find some option in energy saving to let it stay connected.
Ok, your tv cannot receive commands if the network is lost. The problem is here. You have to search around this. Try to limit energy saving in your settings searching about network.
Try searching Settings Network Remote start Set it ON
Are you keeping the TV in sleep mode or Turning it Off totally. Voice Assistants can turn them ON only when they are in sleep but not when Turned OFF totally where the TV is no longer connected to the Network.
Does it have option for chromecast-built in to turn on tv? Try enabling that
I think you need this " Xiaomi Mi AI speaker ",can find how to use it easily on youtube.