Resend invitations to share a calendar on iCloud.com
If you want to encourage your invitees to respond to an invitation, you can resend invitations to all or selected participants at any time.
In Calendar on iCloud.com, click the Share button to the right of the calendar’s name in the sidebar.
Do one of the following:
Resend an invitation to a private calendar: Click an invitee’s name, then choose Invite Again.
Resend an invitation to a public calendar: Click Email Link, type the participant’s email address in the To field, then click Send.