When using the Roku app on my Android phone for private listening, keeps disconnecting from TV, telling me "device not found in network". My network and Roku are up to date and after watching tv on private listening it constantly disconnect from TV, I close app and reopen it, but only last a few minutes. I uninstalled and reinstalled the app, but still the same. I read many reviews on Google Play with same problem, please fix this or I will uninstall the app for good.
Try clearing the mobile app cache on your Android.
From your Android, Settings/Apps/[choose Roku]/Storage/Clear Data or Clear Cache.
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Uninstalling and reinstalling apps on mobile devices will normally retain cached memory. Good practice to clear any Data and Cache prior to uninstalling any mobile app, whether you plan to reinstall the app or not.