If you have leads on a spreadsheet and when you upload them, do you still have zero leads in your campaign?
This is most likely caused by your spreadsheet not being saved in CSV Format.
This article shows you how to save your leads in CSV format.
If you are using a Mac, you must save your leads in Windows CSV format.
If you still can not upload your leads, please contact our support team by sending an email to firstname.lastname@example.org or call us at 702-66-6835 ext 2.