Enemy stops tracking target when my target goes onto a object.

Hello all, i have currently got a enemy that tracks my player(The target) but when i get my player to jump onto a object the enemy stops tracking it does anyone know why this is happening?

Ok dont worry i have found a solution, i dont know why it wokrs but iut does, in the navigation tab go advanced and set the voxel size to 1 and my enemy now tracks me even when i am on a object.