The Google Assistant or built-in MIC feature cannot be used after changing the language setting.

If you update to the latest software and change the language setting, the Google Assistant may become voice search, or the built-in MIC feature may become unavailable.
This is because the Google Assistant and “OK Google” detection features are not supported depending on the language.

From the language setting, select a supported language for each feature.

• The Google Assistant
  Supported countries/regions/languages and how to use the Google Assistant
• Built-in MIC feature
  Supported languages and how to use the built-in MIC (only TVs with a built-in MIC)

NOTE: The display of the language setting will change after updating to the latest software.
Built-in MIC function is available on some models.