Unable to use API to register for on-demand Webinars

We have set up a series of webinars and set them all to be “on demand”. They all require registration.

When I use the API to register attendees it works fine - up to and including the day of the webinar. But the following day any attempt to register someone for the event (so they can watch the recording) generates an error. The message indicates “Webinar is over, you can not register now. …”

However, as expected, if I manually attempt to register and view the webinar it works just fine.

Why will the API registration not work?

API being used is
POST /webinars/{webinarId}/registrants

Hey @zoommeeting,

Is this a recurring webinar? If so, have you tried adding the occurrence id?