Zoom Now Requires a Passcode or a Waiting Room
Starting September 27, 2020, Zoom now requires either a passcode or a waiting room for new meetings. If you haven't had either enabled, a waiting room will automatically be enforced. You can find more information over on Zoom's FAQ: FAQ Meetings Wait Room and Passcode Requirements, September 27, 2020
You can relax these restrictions a little by allowing people in the same account to bypass the waiting room. In your Zoom account's Settings page, you can update some Waiting Room Options. The "Who should go in the waiting room?" option, accessed by clicking the "Edit Options" link, can be set to "Users not in your account". This will allow other users on the Vanilla Zoom account to join your meetings without a passcode or requiring them to be let in from the waiting room.