Struggling with Photoshop again

#Letter365 No94 goes in the box
No94 goes in the box

I want to post this before midnight but can I do a simple image adjustment on the picture of the envelope back. No! Once again I fail to see the logic and cannot make it do what I want. So much for my new-found confidence with it. Perhaps I’ll add it later.

Someone has got to buy today’s as I somehow missed taking a photo of the piece itself. Maybe I didn’t do a piece and the envelope is empty. Now there’s an idea!