Teleportation area doesn't work (only work on some parts of scene)

Hi, I met the issue when I intend to teleport to anywhere in the scene, I added teleport area to the “Content” but it only allows me to teleport to those buildings, vegetations except for “terrains” even if I added teleportation area to the “terrains” itself. Could anyone share any hints on how I can resolve it? Thank you!
My issue is like

Hierarchy of scene is like