I just updated mine, pretty simple, just follow the directions. Or a Nikon dealer can update for you. Just be sure you install a fresh battery, and don't turn off the camera during the updating process. I got a wrist slap because my battery was sub-par, ie I got a message from my camera to install a fresh battery before the  update will take place.
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Today Nikon released a minor firmware update that has to do with the time zone settings for almost all of their current cameras:
New Nikon firmware updates for the D850, D750, D500, D7500, D7200, D5600, D5300, D3400, B500 and P900 cameras. By [NR] admin | Published: June 7, 2018

downloadcenter.nikonimglib.com/en/download/fw/279.html

Nikon D850 Ver. 1.02

Nikon D750 Ver. 1.13

Nikon D500 Ver. 1.15

Nikon D7500 Ver. 1.01

Nikon D7200 Ver. 1.04

Nikon D5600 Ver. 1.03

Nikon D5300 Ver. 1.03

Nikon D3400 Ver. 1.13

Thanks.  Updating now.

I didn’t do the last one on my d7200.  What does this do for me?

It'll do the last updates (added some AF-P lens compatibility and other fixes) plus the current one fixes some bugs in the time/date menu and metadata.