Problem with animation sync with Avatar Mask

Hi,

I have got a problem with synchronizing an animation in Animator using Avatar Mask.
When mine character stops aiming, the lower body is changing the animation to normal running. But the upper body has a problem with that. It ain’t synchronizing, and probably the upper animation is a little bit delayed. I don’t know how to sync it.

Transition of lower body: [BlendTree Running] => [Normal Running]
Transition of upper body: [Aiming] => [Shooting] => [Normal Running]

After changing the mode from aim to normal run, the hands of my character are shaking (I mean it look like drunk-run or sth)

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