Been playing since last year and never earned any points whatsoever towards increasing rank name (soldier, sergeant etc). Same with my friends who I play on xbox with. Don’t desert matches and win regularly so why is it never upping my rank?
They changed how ranking works a while ago.
You need to click your portrait and head to the ranks tab at the top. You now have to manually click the rank up button. It doesn’t do it automatically.
I’m not in front of my PC atm, so I can’t provide a screenshot of where you need to go, but hopefully my description helps somewhat. 
Actually, thinking about it, what I said refers to the rewards for ranking up.
Yeah, definitely no clicking of the ranks.