Top Talent achievement is not working

Finally... here's how I did it:

Currently, to get this achievement, don't use the companion app (log out, maybe delete user data too -- but no need to uninstall it entirely). Just level a strike team exclusively from inside the game. Once the last mission is finished and the lvl 20 level-up happens, go to Prestige >> Challenges. A short pause will happen while the game is syncing stuff, and then origin should pop the achievement for you.