Problem when importing character animation from Maya

When I tried to import my animated character from Maya through FBX, I saw several parts of the character body, such as chest, neck, and head, did not move at all. (The hands and feet worked fine.)

I also saw the character’s head ended up with a low poly mesh in Unreal.

How do I fix these issues? Also, here is [my Maya][1] file if anyone would like to test. Thank you for your help.!

[alt text][3]