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As per Microsoft Excel behavior, when a pivot table is added in a range where already data exist then the conditional format address in that range will be split into range above and below pivot table. This is the reason for the conditional format address change in the worksheet. So, we suggest you to set the pivot table location below the pivot table data range. The following notification pop up will be displayed in Microsoft Excel when this scenario occurs.
If you click “Yes” then the data will be changed, otherwise the pivot table will not be inserted.
Please let us know if you have any other queries.