Help with date in Json

Jsanjur

You cannot use the extended columns in lookup in JSON formatting. You can only use the lookupId & lookupValue (Main value - Name).

From documentation: 

The lookup field object has the following properties (with example values):

{
   "lookupId": "100",
   "lookupValue": "North America",
}

You can only use the value of column you selected in lookup settings - In this column:

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