Leg right IK bone acts strange [FIXED]

I’ve just imported my animations from blender and noticed that walking animations looks strange. My right leg on some keyframes just transform in strange way, it works fine/smooth in blender. Any idea what that may be?

Of course I’ve imported mesh with skeleton so it should be fine right?

Video [video]

EDIT:

Looks like this community forum is dead, but I’ve found solution :slight_smile: My bones were too “erect”, I’ve lowered pose and it works perfect.