My wifi is up and working. My phone is connected to the home wifi. The TV is off. The mobile app refuses to sync to the device and wake the TV. Tried manually and it told me there was no device to pair.
If you do not have the "Fast start" option enabled on your Roku TV, the set completely powers down when you turn it off. When it's completely powered down it kills the wifi connection, so the Roku app on your phone can't find your set on the network.
The Fast start option will put the set into a low power standby state instead of powering down completely, enabling it to start up MUCH faster. It will also keep the set's wifi connection intact so the phone should locate it on your net.
Settings > System > Power > Fast TV Start
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