Drag Selecting UV Shells in main view port no working

[Anonymous]

        Okay so my problem is , Running through a Flipped Normals tutorial and what I need to do is drag select the left side of my character model to select all the shells, and move them up one UDIM so that I can be finished with the UV's. Problem is no matter how I select it nothing happens. 

I've already tried:

• turning maya off and on
• changing preferences from (click drag selection) on and off to see if it did anything

what I can do is:

• Tap click directly on the UV shells outside of the view-port. And hold shift while I do it to have multiples selected.
• problem hear is I can't select inside a my characters mouth to get at the copied UV's there. 

Please send help thank you!

[botchiball]

I have this same issue in 2025.  Using Marquee selection with "Camera-based selection" set to on, I cannot drag select UV shells.  Neither add or remove works (shift or control).  I can only single click, or single click plus add or remove.