We have only one List in mailchimp and the First Name and Last Name are marked as visible. But I don't see the fields in the import task in Skyvia during mapping. What could be the reason?
Probably, this could be the reason of this issue: https://support.skyvia.com/thread/missing-column-mapping-when-using-csv-by-ftp-import-to-mailchimp/?order=all#comment-1369bf5b-2d9c-4e49-8cc3-a9130109e5b8
After checking this, open your MailChimp connection in Skyvia and click the 'clear' link for Metadata Cache parameter.
Please tell us if this information helps.