When importing and merging multiple Excel files, duplicate column names are created

Issue:

When importing and merging multiple Excel files, duplicate column names are created. Later, when trying to select and delete columns, the following error message appears:

"Names must be unique"

Workaround:

  1. Click the “+” button next to the step where the error occurs.
  2. From the menu that appears, select “Other” and then choose “Clean up all column names.”

  1. In the dialog that opens, select “Legacy” under the “Method” option and click “Execute.”

This will automatically append suffixes to the duplicate column names, making them unique.