adobe light room vignetting highlights not working

[DFlo]

The feature for highlights in the vignetting tool is currently not working. I ahve the lates update installed as well. IS there a fix or pending update to resolve this issue. I noticed from otehr posts done years ago that this has been an issue in prior release cersions. 

Thanks

[GoldingD]

Please post your System Information as Lightroom Classic (LrC) reports it. In LrC click on Help, then System Info, then Copy. Paste that information into a reply. Please present all information from first line down to and including Plug-in Info. Info after Plug-in info can be cut as that is just so much dead space to us non-Techs.

[Todd Shaner]

The Post Crop Vignetting Highlights slider only works with negative Amount settings. Is that working?