how do I reconnect to a lost signal?
Are you saying that your Roku device doesn't see your network? Or it does see it but won't connect to it?
What Roku model number? Settings > System > About
Is your network broadcasting on 2.4 GHz, 5 GHz, or both? And what channel?
DBDukes
Roku Community Streaming Expert
Note: I am not a Roku employee.
If this post solves your problem please help others find this answer and click "Accept as Solution."
... or might you be saying the TV is now telling you there is no signal when you switch it to display the HDMI port to which a Roku device it attached?