FBX Animation is completely wrong

I’ve created a simple idle animation for my character. I export it as FBX (from Max) and import it into UE4. Now, the animation looks like a watered down version of what it was in Max.

It goes to the middle of the animation, reverses and then loops. The animation is also 50% of what I did in Max. What I mean by that is that most bones just barely move or don’t move at all and it seems to be slowed down as well.

3DS Max

UE4

See how most of the animation is just straight up missing and it reverts at the half.

Even reimporting the FBX back into Max and it still looks normal, so why does EU4 mess it up?