Masking Not Working

I am suddenly unable to use subject, background or People masking in Classic. I was on v 13.5.x, rolled back to 12 and still had the same issue. Moved back up to 13 and it seems to sometimes work but not consistently. Machine hasn't changed, 2021 MBP with an M1 chip and 16gb RAM. Has been perfect until now. Example of the issue and LR specs attached, please help! I couldn't get a longer video but it does the same thing on almost all photos. Selects most or all of the back/foreground in addition to the subjects, and it used to be almost dead on with any subject.

Lightroom Classic version: 13.0 [ 202309270914-5a1c6485 ]
License: Creative Cloud
Language setting: en-US
Operating system: Mac OS 15
Version: 15.0.1 [24A348]
Application architecture: x64 (emulated)
Logical processor count: 8
Processor speed: 2.4GHz
SqLite Version: 3.36.0
Built-in memory: 16,384.0 MB
Real memory available to Lightroom: 16,384.0 MB
Real memory used by Lightroom: 1,563.2 MB (9.5%)
Virtual memory used by Lightroom: 48,551.8 MB
Memory cache size: 579.6MB
Internal Camera Raw version: 16.0 [ 1677 ]
Maximum thread count used by Camera Raw: 5
Camera Raw SIMD optimization: SSE2
Camera Raw virtual memory: 927MB / 8191MB (11%)
Camera Raw real memory: 997MB / 16384MB (6%)
Standard Preview Size: 3024 pixels
Displays: 1) 3024x1964

Graphics Processor Info:
Metal: Apple M1 Pro
Init State: GPU for Export supported by default
User Preference: Auto

Application folder: /Applications/Adobe Lightroom Classic
Library Path: /Users/catcar/Pictures/Lightroom/Lightroom Catalog-v13.lrcat
Settings Folder: /Users/catcar/Library/Application Support/Adobe/Lightroom

Installed Plugins:
1) AdobeStock
2) Aperture/iPhoto Importer Plug-in
3) Flickr
4) Nikon Tether Plugin

Config.lua flags: None

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