Any time I've had wifi connection problems, including ones where all my other devices connected without issue, they've been fixed by first restarting the wifi router, then when the router comes back up, restarting the Roku. You may then need to set up your wifi connection again. iI really don't understand why this helps, but it has worked for me several times.
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Do not ask me support questions via private message -- post them publicly to the Community where others may benefit as well.
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