You can't resend a signNow invite for a single specific document. But if your recipient never got the invite email for some reason, you can cancel the existing invite, and create the new invite right afterwards. To cancel the existing invite - use this link and to send a new invite, use this link. For document-groups you can use this POST call. It resends invite emails to those with pending invites for the group invite. Resend can also be used to resend invites to a single user if the user's email is specified in the POST JSON body.