keyer screen inside a roto mesh

hello everyone
I’m trying to figure out where I’m wrong but I don’t see errors:
I’m trying to remove the green screen from two images and combine the subjects on a new background, but what happens is this, any advice?
this is my project:

with keyer in screen mode i removed the green screen but when i select a mesh with roto, a black background appear around the mesh…
Thank you

can anybody help me?

Can you share the project and files?