Option 1: Mark invitee(s) attending from the Invite List
If you're using an Invite List, and an Invitee has RSVP'd to you outside of RSVPify, you can choose to mark invitees as attending or not attending.
Go to the Invite List tab
Select the invitee(s) you want to mark attending or not attending
From the Actions menu, select the invitee's reply
Follow the on-screen prompts
You can optionally add and edit guest details such as responses to custom questions or meal preferences after you've manually RSVP'd for a guest.
Option 2: Submit registration using your own form
You can submit a registration in place of your guests by going to your event's URL and submitting a registration as if you were that guest.
Simply click on the View Event button and go through the registration process.
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