Zoom Webinar API: Registrant Limit Error on All Webinars (Despite 0 Registrants)

Hi Zoom Support,

We are encountering a blocking issue when using the Zoom Webinar API (`POST /webinars/{webinarId}/registrants`) to register attendees.

For all webinars — even newly created ones — the API consistently returns:

"You have reached the limit for the number of attendees you can add. Contact Zoom Support for more information."

Important context:
- We are on a Zoom Webinar 1000 license
- This issue occurs specifically during the Webinar API registrant creation step
- Zoom dashboard shows 0 total registrants (Approved: 0, Denied: 0)
- Registration setting is set to Automatically Approve
- The error occurs even on new webinars
- We are not reusing old webinar IDs or emails beyond expected limits

Additionally:
- Our frontend architecture uses Zoom Meeting SDK (meetingsdk-web v3.13.1)

We suspect this is a backend-level lock or stuck cap affecting our account globally.

Please assist with clearing any backend attendee cap or advising how to restore registration functionality.

Thank you 🙏