Webhook does not work in some specific users

Format Your New Topic as Follows:

API Endpoint(s) and/or Zoom API Event(s)
meeting.created, recording.completed

Description
We can not receive webhook in some specific users.
user succeeded in receiving webhook: lmku…VHmA
user failed in receiving webhook: HWgV…NBNg

Error?
We does not receive error, but it seems webhook request is not sent.

How To Reproduce
Steps to reproduce the behavior:
※ This Issue can be reproduced in some specific users
1. Create scheduled meeting
2. webhook request is not sent