My Roku was originally set up using WiFi inadvertently by my partner in our office. We cannot us our WiFi with security in our office. We have connected the TV to Ethernet only. The Roku has been reset and unplugged, replugged in. It continues to only see the wifi network as an option.
We cannot use this until we get the stream on our Ethernet line. But no matter what we do the Roku refuses to see the Ethernet.