Additional features, settings, or issues not covered by specific Microsoft Teams categories
Hi @David Buggy
Teams tag is mainly focused on the general issue of Microsoft Teams troubleshooting. According to your description, your question is related to Teams Development which is not in our support scope. To better help you solve your problem, please add the Teams Development tag to your post.The following suggestion is for your reference:
There is currently no way to create webinar registrants through the API and PowerAutomate.
You cannot create a webinar via the API and you cannot create a webinar registrant. However, you can get the created webinar information through the API, and you can also list the registrants who have created the webinar through the API.
To get this feature more quickly, you can send a feedback directly to Microsoft Feedback to add it in future updates.
Many features of our current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future.
Thanks for your understanding and support.
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