Hey @alex1 welcome to the Zoom developer community.
Are you using the iOS SDK? If yes, could you change the topic to the SDK please?
If not, I assume you’re using the Create Webinar REST API to create the webinar and I see the property approval_type you’re referring to with value “2” indicating registration not required.
To be certain I understand all the parameters, could you provide the specific POST request complete with headers (just omit any tokens or PII please) so I can try to recreate this issue and diagnose the problem?