You bought return where someone switched out the remotes. Take it back complain to walmart. Or just purchase voice remote for $20 from walmart and pair it to the Soundbar. If your Roku soundbar is Onn Smart Roku Soundbar, this is what remote supposed to be:

Which is IR remote, not wifi like the voice remotes are.
Unless you bought under $50 Onn soundbar from Walmart that is only Roku Tv ready, and not a true Roku soundbar, because they have built-in roku streamer?
Edmund
Roku Community Streaming Expert
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