Whilst we strive to support the functionality of all applications, due to the large differences in app developers and system requirements, we simply cannot guarantee that 100% of third party applications will be compatible with your TV.
It appears that the Netflix application does not correctly recognize the resolution of certain output devices. Netflix has a support article available here regarding this issue, as their team is investigating the cause so that it can be rectified across all devices.
In the meantime, this error is often resolved by reinstalling the latest Netflix updates in the app store. To do this, open the Google Playstore from the Home screen and search for the Netflix application.
Select "uninstall updates", and allow your TV to complete this process. Once this is done, the updates can be reinstalled through the same menu, which may allow the app to correctly identify the resolution of your TV.