Riley18
The 3820 has a Long-Range Wireless Receiver (LRWR) in the power supply cable that is responsible for communicating with both the network and the remote. (it creates a private, hidden network for the remote to connect to).
It is possible that either the LRWR is failing, or that your Voice remote may not be working. (not able to find the hidden wi-fi direct network).
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I think I would probably try a new remote first (since seems like the Stick is connecting to internet) and see if that resolves issue. The Voice remotes start at $20 (can be found at Roku online and at Walmart, Best Buy, Target, etc) but currently the 3820 is on sale for $35, so almost makes sense to get a whole new device. (https://www.roku.com/products/players)
If your 3820 is less than a year old, should qualify for replacement under warranty https://support.roku.com/article/208757058
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Personally, I would probably run to the store, grab a new Voice remote (or a new Express 4k+ 3941 or Streaming Stick 4k 3820) and see if the new included Voice remote connects to the existing 3820. If so, you narrowed down to bad remote and now have a spare device for the extra $10-15. If still doesn't connect, then you may have a bad LRWR cable. (these can be found at Roku for $20. (https://www.roku.com/products/accessories/usb-power-cable-with-long-range-wifi-receiver-streaming-stick-4k-and-4k-plus)
The LRWR is primarily the reason I do not care for the Streaming Stick models. This proprietary cable just adds one more troubleshooting obstacle and part that can break/cause issues.
