Background Eraser Tool Not Erasing 100%

Hey all,

I am using the Background Eraser Tool and it's not erasing at 100%. I have listed my steps below to recreate the problem. My goal is to extract the subject from the background.

Photoshop Version 2023 V 24.1.0 

MAC OS Monterey 12.4

1 - Select Background Eraser Tool.

2 - Check Background Eraser Tool Settings are set to (Sampling: Background Swatch, Discontinuous, Tolerance 80%, Protect Foreground Color is on). 

3 - Use the Eye Dropper Tool to sample the hair color to protect it and not erase it.

4 - Begin erasing the unwanted area, which is the white background. Every time I sample a color and erase, I can see my brush strokes. See the image below and you'll see different shades of red. Which shouldn't be there. It should all be the color of the red background layer.

5 - Select the subject  (select > subject)

6 - Use Polygonal Elaso Tool. Make sure settings are set to "Add To Selection"

7 - Select the area outside of the head that I erased to add it to the selection.

8 - Invert selection "ctrl-shift-i"

9 - Hit Delete

10 - Deselect subject "ctrl-d"

You can see the exact area I selected didn't actually delete all the way. Anything outside of that did delete as it should.  I don't know how to explain it or know why it's happening. But that selected area should definitely be deleted and match the red background. I have completely uninstalled Adobe Photoshop and reinstalled it too.

Any help would be greatly appreciated.

Thank you!!!