To get this Achievement you must spot an enemy who is at the Top Mid part of the map.
Check your controls in settings to make sure that spotting is actually assigned to a button.
The following maps have a Top Mid location: Behemoth, Aquarius, & Catalyst.
⬇️ Timestamps ⬇️
0:00 Behemoth Location
0:47 Aquarius Location
1:01 Catalyst Location