Okay, so i have been very busy lately with unlocking some uniforms and stuff.
So when i finally achieved the requested 25 avenger kills stage 2, which unlocks the Ranger Operator uniform, it said in the game summary that i had it.
But when i took a look in "Create a soldier" in the uniform section, it remained locked and it even said i needed a different operation fulfillment than i already had.
Does anybody else has the same or a similar problem?
On blops 2 I had a similar problem when I completed 2 challenges and got the notification during play but it didn't record when I went back to barracks. I contacted Activision online chat and they got it sorted. Try it and good luck.
I do know that these operation unlocks can be for certain genders. Try checking for the Ranger uniform, both for male and female and let me know if you see it!