Note also that you need an admin account to do this.
If your organization has requirements for custom Lead or Contact fields, it may not be possible to upload business card data to Leads and Contacts. However, you can set a default value for the required custom fields. Logged in as an admin, go to the configuration screen and set default values for each custom field. You can also designate a default Record Type and Lead Source here.
Also, if you enable ”Allow users to overwrite default values for custom fields,” users can individually edit custom field values when uploading card data. See here for more information.