Some messages sent to the channel via Zoom Team Chat API not delivered

API Endpoint(s) and/or Zoom API Event(s)
endpoint to send message: /chat/users//messages
endpoint to get message: /chat/users//messages/?to_channel=

Description
I’m working on a notification system based on Zoom API. I noticed that not all messages are delivered. I created a test to send 100 notifications with some delay(500 ms) to the specific Zoom channel. Usually, that test has an undelivered messages gap. For example, messages #1-#60 are delivered, messages #61-#81 are not delivered, and messages #82-#100 are delivered again. The UI presentation of that gap is attached.

Error?
When I request the messages by ID, for undelivered messages, I receive a response with code 400

How To Reproduce
For each request to create a message, I receive a response with status 201 and the ID of the message, but when I later try to get those messages from Zoom API - for delivered messages, I receive information about the message, and for undelivered messages, I receive a response with status 400.

Hi @eugenes
Thanks for reaching out to us and welcome to the Zoom Developer Forum!
I am happy to look further into this.
I will send you a DM so you can send more data about this issue, such as the screenshot you mentioned and also some requests ids so we can track this issue