Send password but leave existing data untouched

Hi
How do I upload a CSV of existing users, only containing their new user names and passwords, but leaving their other fields blank, without deleting their existing user data?

The setting I use is “leave the old value for metadata”

in my CSV file upload, “Username” has data “email address” has data & “password” has data
But I keep the “Name of Business” field blank & “Business Description” blank, and this then deletes the users existing “Name of Business” “Business Description”