when the background is applied photoshop distorts all the subject including the face

Having made the selection properly, when the background is applied photoshop distorts all the subject including the face, this happens alot. Two upgrades earlier this was more stable version.

Does anyone have an idea in Beta  of how to fix this? I´ve been trying many things, but it keeps messing up with the subject. 

The steps:

I selected the subject and arrange it in the areas that I wanted, then I Inverted the selection and add a simple prompt "cliff with stormy sky" for the background. 

Im playing around with Beta and the biggest issue so far It´s that you can´t substract the subject from the background once the background is applied, if I try to modify manually the subject I also modify the background image.  The ideal thing for me is that photoshop could be able to separate the composition in two layers, one with the new generated background and in other layer the subject that I already selected, both with a mask so I can work on the subject and the background in a non destructive way. The images that are generated by photoshop need to be editable.

Photo number 1 its the one with the background, the final image and photo number 2 It´s just my selection of the subject.

Photoshop Beta Version 25.1 m2316