Applying column formatting hides list value

Hi all,

I'm just getting into column formatting.  I'm trying to create the https://docs.microsoft.com/en-us/sharepoint/dev/declarative-customization/column-formatting#create-clickable-actions that was on Microsoft's site explaining Column Formatting in Modern SharePoint Sites using  JSON.   the example itself is very straight forward, but when I apply it all values in the column disappear.  (See below) There were values in the column before applying the formatting.  

I tried to recreate the same formatting on my Office Developer SharePoint subscription and I had no issues applying and seeing the formatting.

Any suggestions why I wouldn't be able to apply column formatting on an on-prem 2019 server, but I can apply it to an SP online list?  I did update the schema to account for SP 2019 as specified in the documentation ("$schema": "https://developer.microsoft.com/json-schemas/sp/v1/column-formatting.schema.json") 

Thanks in advance for you assistance. 

M