Hello @KarenP8174 ,
At this time, it is not possible for you or the registrant to edit guest info (including adding / removing them). If the registrant needs to add guests, you'll need to cancel their registration and have them re-register.
If your event requires payment for items or attendance and they've already paid, they can submit their registration info, then exit the form once they get to the payment confirmation section. After that you can manually update their new registration to Attending and their payment status to Paid, to avoid having to do a refund and forcing them to re-pay.
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