See solution in other versions of Excel:
Question: On a pivot table, how do I remove grand totals for columns in Microsoft Excel 2013?
Answer: Below we want to remove the grand totals for the Order ID columns.
To remove this column grand total, select the DESIGN tab from the toolbar at the top of the screen. In the Layout group, click on Grand Totals button and select On for Rows Only from the popup menu.
Now when you return to the spreadsheet, the grand totals for the Order ID columns will no longer be visible.