Thanks for posting here in the Community.
Try these simple tips and troubleshooting steps as this may help with the connectivity issue:
1. Restart your router (even if other devices have no problem finding and connecting).
2. Restart the Roku to clear its memory via Settings > System > System restart
3. Find and connect to your network via Settings> Network > Set up the connection
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.
For more information on troubleshooting connectivity issues, please refer to this link: How to connect your Roku® streaming device to the internet using Wi-Fi® or Ethernet | Official Roku ...
Let us know if there's any difference after.