Agm 65 lock issue?

For some reason my agm65s do not tanks out as far as they used to. Before, i could lock maybe 6km out. Now, i cant lock until about 3-4km out. Was there a ninja nerf or something?

if its u.s it aint gonna work. like when i have a tank in my sight i press lock, and it locks onto the ground instead of the tank.