paticipants_info -> id is not coming with participants API

"report/webinars/#{zoom_api_uuid}/participants?include_fields=registrant_id", account_id: zoom_account_id

We are taking leave_time only if id is present in the participants response.

for few users we are getting participant_user_id and id. But for few users we are not getting. Help us to understand what is the reason.