Foliage disapearing under the camera

So it’s my first time using Unreal, and I’m actually working on a porfolio scene. I’ve done some grass in speedtree to make foliage in Unreal and after importing and making the foliage, I find that the grass disappears when under the camera, and the more far away you go the more disappears. It’s strange because normally it works the opposite way, those who are far away from the camera are the ones who disappears…
I’ve been searching other post to find the answer but with no luck. I’m actually thinking that it’s something related to the LODs, but not really sure.

(This is when you look to the front)

(This is when you look under the camera)

(This is when you put the camera to the ground level)

Hope you can help me!