The issue to your question has nothing to do with the
It is about your reference to the sheet.
You need to enclose the name of the sheet in single quotes, because the name of the sheet itself has a blank space between the words.
As from the official help site on "Get data from other sheets in your spreadsheet":
If a sheet name contains spaces or other non-alphanumeric symbols, include single quotes around it
In your case use
'Retail Sales'!G9:G39 and surround this with double quotes.
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