I've run into this here several times. This has always worked for me:
If that doesn't fix it, try disconnecting the power to your Roku for a few seconds. When it comes back up, see if you then can set up the network connection.
I have literally done it all... I’ve rebooted, restarted, disconnected power, and tried deleting apps. I’m at the point that I am resetting to factory settings and now it won’t let me...
I’m at a loss. Wtf...
I have two TV's using Roku Streaming Stick+ devices. Both worked fine for several months, then one began having issues with displaying Netflix and Prime movies. Checking the network connection (Settings/Network/Check Connection), the WiFi signal strength indicated "good" but the internet download speed was "poor" measuring 0 - 2 MBPS. The other TV/Roku combination was physically further away from my wireless router and on a different floor of the house, but measured an internet download speed of 45 MBPS. I chatted with Roku support several times, and they felt it must be an intermittent internet problem. Switching Roku's between TV's did not solve the problem - the TV closest to the router was always the one with the poor signal. Finally I switched the power cords that lead from the USB port on the TV to the Roku stick, and the problem followed the power cord. Turns out the power cord also contains an "AWR" (Advanced Wireless Receiver) which is basically the WiFi antenna for the Roku stick. When I chatted with the Roku help line again, the representative checked and it turns out that faulty AWR's are a known issue and Roku agreed to send me new ones. Problem solved!
Mine is having the same issue since the update. Chat person said it "can't be a roku problem because it connects to your mobile hotspot" but everything else I own connects to the internet just fine. The roku won't even connect with a wired connection.
yeah, they don't make it easy.....click on Support/Support Home. Then click on "Setup and Troubleshooting". Scroll all the way to the bottom of the page, and right above the purple banner, on the right you will see "Agent Support" and under that, you click on "check support options". In the drop-down menu that appears, select "questions about setup or using my Roku" and click "Continue".
Now, you have to select a product, and some do not give you the chat option. I have a Roku Streaming stick+ and that one does have the option to chat with a support person so I would pick that one if your's does not give you the option. Next, you have to select an issue - choose "wireless network setup and reliability". Ignore the menu that appears and click the purple button (lower right) that says "Need More Help". That will FINALLY take you to a page where you can contact customer support by chat or email.
Like I said, they don't make it easy and don't ask how I figured this out!