Need help with blending 2 photos

[Mell Råmone]

I was trying to get rid of a wall shadow on a portrait photo and couldn't figure it out so I selected the subject and selected the background as 2 separate photos and merged them, but where the shadow was it's now transparent. Every time I use the colour match on the background and try and colour it in it just draws in transparent. Not sure what to do or how to fix this.

[sishamIAGD]

Can you show us what you mean with some screenshots..?

[c.pfaffenbichler]

Asking for advice on editing specific images but not showing them … 

Could you please post screenshots with the pertinent Panels (Toolbar, Layers, Options Bar, …) visible of your current montage? 

And the two original images (in lores and blacked out face if you prefer)?