It goes Ragdoll because it simulates physics now.
I think you wants mesh to push other Physics Objects, but not being pushed by or ragdolled.
To do so, you need to set ‘Physics transform update mode’ as ‘Component transform is kinematic’.
The default is ‘Simulation Updates Component Transform’
If u want to set does settings per bone. (like the body is controlled by animation, but hair is physics simulated)
You can change ‘Physics Type’ inside Physics Asset.
There is
Default : It will follow Skeletal mesh’s setting
Kinematic : It will ignore force from outside, and only follow animation.
Simulation : Basically ragdoll
Or u can just set ‘Simulate Physics’ value of skeletal mesh as false. To turn off any physical interaction.