Happened to me today. I did not read one suggestion anywhere that fixed the problem. So I problem solved on my own. This worked. I downloaded the roku remote app on my phone. Went into settings on the roku. Then to remotes. Then asked to set up a new remote. Hit "pair " on roku, pressed the button on the remote next to the flashing light. It works now!!! Hope this helps someone.
I tried all of the suggestions and nothing worked for me. I have a roku stick and I tried switching the HDMI port to a different one and that finally worked! It automatically paired my remote and started working again.
