Hello @Kashif_Haque! Glad we discussed this and resolved it internally by chat earlier, though I wanted to close the loop on this thread in case others encounter it.
Currently if a JSON column has spaces in its name, like "Order: Discount Codes", then our updated step Expand JSON won’t auto-expand it. While our engineers work on this, please use the step Rename columns to remove spaces in a column’s name for Expand JSON to auto-expand it (like changing its name to "Order:Discount.Codes").