Help Required, relating to Join & Union Results

[JC500O]

I'm fairly new to alteryx and have stumbled in to an issue which I can resolve, hence my reach out to fellow members.
My workflow, requires me to pull the results of 2 x csv files together in order to create a master csv file.

The issue I'm encountering is that the new master record contains all the data in a single file but there is additional headers and nulls being added which is not what I was expecting as shown below.

Note: The master output file layout should be "User_Exteral_Key, Person_Supervisor_List, Is_Externally_Owned, Action" but for unknown reason the "User_External_Key" is being produced twice and is showing "Null"

[Samanthaj_hughes]

Hey @JC500O

The column names are slightly different for this to happen, you can rename them the same before the union. Or in the union tool, drop down to manually organise the columns and shift the two columns under each other.

Enjoy.