JSON to change font from Times to anything else - Syntax??

Drogon365 I have used below JSON & it is working fine for me.

Example:

{
   "$schema": "https://developer.microsoft.com/json-schemas/sp/v2/column-formatting.schema.json",
   "elmType": "a",
   "txtContent": "@currentField",
   "attributes": {
      "target": "_blank",
      "href": "https://google.com/"
   },
   "style": {
     "font-family": "Segoe UI"
   }
}

Output: 

Try using similar JSON styles & let me know if it works for you.

Also, are you using column formatting as well as view formatting in the same list?

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