Zoom Calendar Plugin

I used the Zoom Outlook Plugin to schedule a meeting. Before the meeting took place, I added a new participant to the meeting. Once I hit the Send Update button, this message popped up "The event description will be replaced with the Zoom default invitation". So, now the meeting no longer has the agenda text (event description) that I had originally included (so that attendees would know what the meeting was about).

Any ideas on why this happens and, more importantly, how to prevent it in the future?