Problems when two or more overlapping meetings have been scheduled by a single Zoom Account

For Zoom meetings, the meeting owner is the user who either schedules the meeting or has it scheduled on their behalf. The meeting owner also owns any cloud recording of the meeting.

Zoom does not allow users to own two or more meetings that occur at the same time. This situation might occur when a user schedules multiple meetings, some of which take place in the same or overlapping time slots.

While a meeting owner will not get warnings from Zoom about conflicts at the time that they schedule concurrent meetings. When the concurrent meeting is launched, the owner or alternative host starting it will see the warning message, "You have a meeting that is currently in progress." Zoom will then prompt the owner to close the meeting already running before they can start the next meeting. Doing this unfortunately ends the first session prematurely for all participants. 

To avoid this problem, users are advised to use Schedule Privilege when it's necessary for users to schedule meetings that others will own.

For more information:
Can I host or scheduled concurrent meetings
​​https://support.zoom.us/hc/en-us/articles/206122046-Can-I-host-concurrent-meetings-

What is Scheduling Privilege
https://support.zoom.us/hc/en-us/articles/201362803-Scheduling-privilege