The leaves of a tree I made become white when it's far away

[Iki_GN (iki)]

Hi!
Recently, I made a tree in blender, I exported the leaves and the trunk in roblox.
I decided to add a surface appearance on the leaves. When I’m close to the tree they look good, but when I go away they look white, How can I fix this?

[o4ev]

Please just look into Pixelfix or do anti-aliasing on adobe photoshop