That camera requires at least Lightroom 6.3 or Lightroom CC 2015.3. There will not be any updates to Lightroom 5, so it will be necessary for you to upgrade in order to have support for the NEF files. An alternative would be for you to use the DNG converter to create DNG copies that can be used in Lightroom 5. The DNG converter is free. And you might as well download the latest version.