Unable to advance immortale flames hunting log

[Nekodar]

the NPC for promotion only mentions rank 2 of the hunting log as a requirement. The promotion is for chief flame sergeant to second flame lieutenant

Take a look at rank 3 of the hunting log, and see if you really fulfill all the requirements listed there.
Also check your quest journal to see if you have any stray quests.

I got second lieutenant recently after I ran Aurum Vale as specified by one quest. (Had to run it twice because I forgot to talk to NPC outside Aurum Vale first)