When is uuid not returned in meeting participant reports?

When I query for participant data using this command I see some users returned with id set to “”:

https://api.zoom.us/v2/report/meetings/X91IzL2USIe2m0InFqCkqw==/participants?page_size=30

But in What is a UUID it is stated that the UUID (Universal Unique Identifier) is used to uniquely identify all meetings and users.

So why would id be returned as blank for some users here. Also, if id is blank is it safe then to assume user_id is unique for all the users for my given Zoom instance?

Hi Rex,

I will be helping you troubleshoot this issue. Since we would need some confidential credentials from you, can you please file a ticket at developersupport@zoom.us , and send us some screenshots showing the issue?