2 webinair

@club74  – you want to make sure the Monthly option is selected when you purchase the Webinar add-on. There should also be a checkbox for automatically renewing the add-on, which you likely would not want checked – unless, for example, you wanted Webinars for two or three months, in such case, check it initially, but come back to your account billing settings later and check it where you’re done. 

This Zoom Support page might also be helpful. 

Thank you 🙂