"Select duplicates in..." should NOT select dupes in subfolders, if the subfolder is underneath the selected folder.
But it does.
Example, there's a dupe in these two folders. One is a subfolder of the other:
I want to delete the dupe in the parent folder, and keep the dupe in the subfolder.
But i cannot.
If i "Select dupes in" the parent folder:
then the dupe in the subfolder is selected:
How did you set up the search filters?
ie. did you set up a seperate filter for each folder/subfolder with 'Include files only' (and then tick them all to serach), or did you set up just one for the parent directory with 'include files and subfolders'?
Of course you could always manually select the ones that you want to remove rather than using the dropdown, but lets see if we can work out why it's not doing what you expect.