csv file when there is a subfield

[Sammy Orellana]

as income the csv a sub field. example channel is qa environment and is linked with a project visual example

[Andy Heinzer]

Where you use the term 'subfield', I think it actually referring to what we call a cascading choice custom field.   The way this has to be formatted in your CSV file is explained in Importing data from CSV:

Importing cascading choice custom fields

You can import values to a cascading choice custom field using the following syntax:

Summary, My Cascading Custom Field
Example Summary, Parent Value -> Child Value

The '->' separator allows you to import the hierarchy.

I hope this helps.

Andy