What model number is written on the device? If it's a stick with a USB cable with a "bump" in the cable you must use that cable and they are known to go bad. That would explain both the "No connection" message and the non-working remote. As a first thing to try, remove the cables and reconnect them.
Roku Community Streaming Expert
Help others find this answer and click "Accept as Solution."
If you appreciate my answer, maybe give me a Kudo.
I am not a Roku employee.
