It looks like something changed recently and it broke how our users would normally create meetings (using our app) without a waiting room.
In Zoom preferences I have Password=On, Waiting Room=off, and if I try to create conference in Zoom - all is ok. But from yesterday, when I create the same conference with our app - I get right the opposite (Password=Off, Waiting Room=on).
Thank you for reaching out to the Zoom Developer Forum. It sounds like some settings may have changed at the account or user level. I would check the account meeting settings and user meeting settings from the web portal to see if that was changed.