My additive animation is doesn't working

Help me please, why my additive animation doesnt work, while ovveride animation is working
My video example

and another my theme with Assets Project : Theme

I think it could be cause you have your base layer in ik, and the other isnt?

Did you set a reference pose for your additive animations? The option is really easy to miss and they won’t work without it. Two ways to fix this:

Option A: You have to export your additive poses/loops so that on frame 0 your character stands in the default pose and the actual animation starts at frame 1.
Then, in the animation import settings of your fbx, check the box “Additive Reference Pose”, leave that at frame 0 and change the start of your animation to 1.

Option B: Export an animation clip of your character in default pose.
Duplicate the additive animation clip from your fbx file, so you can edit it. In your inspector, activate Debug mode and drag your default pose clip into “Additive Reference Pose Clip”. Also check “Has Reference Pose”.

Hope this helps!