Serious security problem

Hello. I´m triying to contact ZOOM support but their answers are like they don't read half the message.  (sorry my english if I make mistakes)

 I use ZOOM meetings in my job and I make some private session in wich I want to alloy only resgistered people. But I have discovered that NOT registered people can access to that meetings with the ID and the access code, and it worse, ZOOM knew about that problem!!

Why didn´t ZOOM warn the users?!! 

So I set a recurring meeting with registration. People register and zoom sends an email with the link, the ID and the code. And if the registered people share the ID and the access code to other non registered people, those people can access to the meeting whitout registration. 

What can I do to fix that? I mean, I only want to allow my meetings the registered people. No matter how they accees to the meeteing

Thank you

best regards