FABRIK: Strange pawn behavior

I’m using FABRIK and my pawn has strange behavior. You can see this on the below video:

Please help me.

Change the FABRIK node’s Effector Transform Space to Bone and select the Effector Transform Bone to be your foot. For leg IK it’s best to use two-bone IK node because then you can also set a joint target location.

Unfortunately it doesn’t helped me, my pawn still has strange behavior, other but still not good…