To view a list of contacts by the user assignment:
Navigate to your contacts list page by clicking on “Contacts” on the left-side panel.
Click on “Filter Contacts.”
Click on “Assigned to” within the group of fields you can filter by.
Start typing the name of the user you want to view and select the user.
Click “Add filter.”
When the list filters, you can then click “Export” from the “Import/Export” panel to export the list into a CSV file.