Could you please describe in more detail which data is not being shown in Lightroom from Nikon D750?
What is the format of the files: raw of jpeg?
Which Lightroom version do you have?
LR CC 2015.5 / 6.5 has a bug and doesn't properly import lens metadata for many Nikons (and perhaps other cameras). See this bug report in the official Adobe feedback forum: Lightroom CC 2015: Lens metadata field missing on import | Photoshop Family Customer Community