See if this helps - it has worked for me numerous times:
Restart your router (even if other devices have no problem finding and connecting).
After the router comes back up, restart the Roku via Settings > System > System restart (for a Roku TV it's Settings > System > Power > System restart) to start with a clean slate.
Reconnect to your network.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you.
Streaming Stick 4K+ 3821 | Streaming Stick+ 3810 | TCL Roku TV 43S245/C107X | Streaming Stick 3600
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