When I've had connection problems not fixed by a manual re-setting up of the wifi connection, I've always been able to recover by restarting the router (even though all my other devices are able to connect without problem), followed by a restart of the Roku.
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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