Terrain collider remains flat after raising or lowering it

I have created a 3D project, added a terrain to it. Textured it. And added an FPS Controller from Standard Assets. I run the project. It working perfectly. Okay, now I have raised the level of terrain on some part and played again. But the problem is this time the FPS controller is behaving as if the terrain collider is flat as before lowering it. Please watch the attached video which shows the problem (I could not attach it here. So I uploaded it to a website. Link to video: http://uploadanotherfile.ml/d/Unity_Issue_Terrain_Collider_Flat.mp4)

Note: I placed the FPS controller above the terrain running each time.

Make sure that your Terrain Collider component has the correct Terrain Data assigned. It should match the Terrain Data used in the Terrain component itself.

If something still bugs out and won’t update correctly, you are usually able update a Terrain Collider manually by saving the scene or by disabling the Terrain Collider component and enabling it again. This method also should work at runtime if you disable/enable the component through a script.