The Newsmax Channel/app has been having more problems as of late. It certainly is nothing you are doing.
If you must have the Newsmax Channel/app, then Remove the Channel, do a System Restart, and then Reinstall Channel. (This will clear out any corrupted cache and install the latest/updated version).
The above will not guarantee the LiveTV will immediately work, but will give you the latest version. Newsmax Channel will just start working again on its own (it short order), once its developers address the latest issues.
If all you want to do is watch the Newsmax LiveTV rather than the recorded programs, then best alternative is to just watch it on the Roku Channel LiveTV (ch 150), Pluto LiveTV (ch 236) or on RumbleTV.
----Newsmax Channel/app used to have an issue maybe monthly, now seems to have an issue with their LiveTV just about every other week). I have removed it from my Roku and now just watch it mainly on Roku Channel or Rumble.
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