Black and white conversion changes to a brown and white?

[#1]

I am converting color images to black and white using the Lightroom treatment "Black and White" and it is turning a brown and white. How do I change this so it creates a real black and white image. 

When I take the brown and white image into Photoshop and use the black and white conversion setting, it changes it to black and white so something definitely needs to change in Lightroom. 

Please help. 

[#2]

I am converting color images to black and white using the Lightroom treatment "Black and White" and it is turning a brown and white. How do I change this so it creates a real black and white image. 

When I take the brown and white image into Photoshop and use the black and white conversion setting, it changes it to black and white so something definitely needs to change in Lightroom. 

Please help. 

[#3]

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.

[#4]

Some inquires

1. What Profile are you applying?

[#5]

2. Just in case, what Process Version is in use?

[#6]

3. Are you doing anything odd to Temp or Tonality?

[#7]

4. No odd Preset?