If Acrobat DC originally opens in one screen and then gets moved to the second screen it will lose some of it's functionality (insert custom stamps, insert references, etc). It's almost like it defaults to out-of-box. If we move it back to the original screen it was opened in, it does not regain it's old functionality.
Would that be possible for you to share a short video clip of what exactly you have explained above?
You can either share the uploaded link of the video or can share the file with us via email. And you can send it to the email that is shared via private message. (Please do mention your forum thread in the subject)