If you want duplicate values to stand out in an Excel spreadsheet, you can choose between two conditional formatting rules.

By using the Highlight Cells Rules, you can highlight duplicate cells in your Excel worksheet to avoid confusion and mistakes.

To extract and sort non-adjacent arrays in your data, nest the CHOOSECOLS or CHOOSEROWS functions inside your SORT or SORTBY ...

If your source data is in Excel and has duplicates, run Power Query to remove those duplicates before running a Word mail merge.