Stretching Bones when simulating Physics

Hello!

I’ve started developing games a few days before with UE4 but have a problem which I can’t solve myself.
When I simulate physics for the Bones of my Mesh, then it falls down but somehow stretching…

My Blueprint looks like this:

So when I press ’ E ', it looks like this:

And btw. here is how my mesh is looking:

Check your physical asset