The easiest thing is to configure your new network to match your old network - same SSID/network name and password. It should connect and you can go back to using the app. The next easiest may be to get a new remote. If you know the old network name and password and you can configure your phone's hotspot to match, there's a way using that and connecting another phone/tablet to the same hotspot and using the mobile app on it acting as the remote to get it connected to the new network.
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