Updating new contact list in the published journey:

Step 1: Go to the Journey section (left panel) and select the kebab menu of the journey under action on the right and choose Enroll contacts.

Step 2: Select Upload CSV under Select Contacts to upload a new CSV file.

Select the list you want to add the contacts to and upload the CSV file -> Select Map columns.

Step 3: Map the respective columns and select Review Import

Step 4: Review the imported columns and select Import contacts