I've had this EXACT same issue for over a month now. It's something related to the 4k pro stick. I had it linked to Google home since day one then out of the blue, Google home said it was removed. I've tried everything listed and everything everyone else has done to try and get it back so don't suggest anything else to me. I'm tech savvy and this is clearly something roku has done.
I've set up another device since then but it was just an HD device to replace another HD device that was failing due to age.
I noticed the setup process between the HD and the 4k pro differ SIGNIFICANTLY when adding them to your account which I surmise is the issue.
I too, have been waiting for WEEKS if not over a month, for Roku to fix this. Every time I respond to the email, I just get the standard response, we are working on this and will have it fixed soon. Soon..... Over a month soon??
Come on Roku. Get your stuff together...
