Not Receiving ZoomPhone Webhook Event (phone.callee_ringing) in Background on iOS

Hello,

We are currently developing a ZoomPhone name resolution application using Zoom Phone webhook.

Issue:
We are utilizing the phone.callee_ringing webhook event to trigger notifications in our application upon an incoming call.
This works seamlessly on desktop clients and Android devices.
However, on iOS, when the Zoom client is in the background, the phone.callee_ringing event is not received. The event functions correctly when the Zoom client is in the foreground.
In the background state, It appears that the client is only launched, and the phone.callee_ringing event is received for the first time when a VoIP PUSH notification is delivered and answered to.

Question:
Is there a recommended method to receive the phone.callee_ringing event at the same timing as a VoIP PUSH notification in the background state on iOS? Alternatively, are there best practices or recommended settings to achieve this functionality?

Thank you.

This case is the closest match to the issue we are currently experiencing, but unfortunately, no solution was provided:

We are also experiencing an issue with Android notifications for incoming calls. The problem occurs when the app is running in the background.
When the app is closed, incoming call events are received normally for a few minutes.
However, after this initial period, (5 minutes or so) no events are sent unless I actively respond to the app.

Is it possible to modify the current behavior to ensure consistent delivery of incoming call notifications, regardless of the client’s state?

FYI: Webex Calling incoming call events are sent regardless of the client’s state.

Thank you.

I can confirm the same behaviour. If I open up a webpage with app dot zoom dot us slash wc slash phone then I get the ringing webhook. If I close that page then I only get a call_log_completed and call_history_completed. Seems like a bug that multiple people are experiencing so should be escalated