@Dazeemcdowell1
If your RokuTV has an ethernet connection, you should be able to connect via ethernet and the mobile app should be able to detect TV. Once connected, you should be able to use the mobile app to change your connection back to wireless.
The Roku device or RokuTV has to have been set up on a network successfully before it can be used with the mobile app. If you have changed networks, factory reset the RokuTV, or this is a new/used TV without a remote and it has never been setup on the network, then will not be able to use mobile app.
If ethernet is not an option, then a replacement Roku Voice Remote or an IR based RokuTV compatible remote can be purchased at Walmart, Best Buy etc to get you back up and going.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102