You've got a real problem since Roku doesn't even make a remote that's compatible with that model anymore. You would only be able to find one on the used market and quite frankly, it's just not worth it. Roku stopped supporting that model a few years ago and it no longer receives updates and newer apps don't support it. Your only hope if you really want to keep using it is to configure your new Wi-Fi to match the last network it connected to (same SSID/network name and password) and hope it connects.
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