When importing your CSV file into Sell you might encounter a 'null contacts were found' error message if your import file is not properly formatted.
Make sure that the column headers on your import file do not have line breaks (or multiple lines) in the title. For example:
The following column header is formatted correctly:
The following column header is formatted incorrectly:
If you continue to receive a 'null contacts were found' error during import error message after correcting your column headers, contact Support, providing them with a copy of the import file.