@lailjason479
If you have a computer/laptop with Windows 10 or Windows 11, you can try using it as the mobile hotspot. (Just configure it using the same name and password as the one you are using now). Then use your phone to connect to the computer/laptop hotspot and that should allow you to once again connect the mobile app back to the TV.
Instructions found here https://support.microsoft.com/en-us/windows/use-your-windows-pc-as-a-mobile-hotspot-c89b0fad-72d5-41...
If using Linux, post back with distro as terminal commands differ.
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Unfortunately, some mobile devices (cellphones), while serving as a hotspot, cannot interact with other devices connected to them. By using the laptop as the hotspot, this removes that limitation.
This methods works best when using wifi and needing to create an ad-hoc mobile hotspot, but with a little tinkering may be able to resolve the issue you are having.
If doesn't work for you, or is too complicated, you can just connect another phone/tablet with the Roku mobile app installed on it to your existing/phone hotspot and then connect that to your tv. (you need at least that 2nd mobile device).
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A third method exists that requires a bit of work. You will likely need to install some sort of "Hotspot Manager" app on your phone that yields the "IP addresses" of connected devices. (this will tell you the IP address of the RokuTV that your hotspot issued). You then use a browser on your phone to go to an old open-source application at https://remoku.tv/ and connect that interface to your RokuTV and using the on-screen remote you can control your RokuTV. (there is also a Help section on that page with more info).
Once you have the RokuTV IP address, you enter it into the Remoku app under the Settings.
Due to security settings, the remoku app can no longer automatically scan for connected roku devices (or shouldn't be able to), but I still use Remoku regularly (especially when needing to copy/paste text and passwords into Roku devices or performing searches).
If your wifi is now back up and running, just use the Remoku app remote to steer the RokuTV back to your regular network connection.
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It would not be a bad idea to purchase a replacement or compatible RokuTV remote though, as it will be needed if you ever need to factory reset your RokuTV for some reason. Walmart, Best Buy, Target, etc. carry some universal streaming remotes for $10-15. (just verify remote is compatible with "RokuTV" which is different than compatible with Roku streaming "players").
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102
