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We're working on a VoIP app using Zoom SDK. The app is able to receive incoming call and show system calling screen using CallKit in any state (background, foreground, suspended, terminated).The problem is the timer function that needs to start running after notification is received. Whenever the app is woken back up from sleep of force-quit, my timer function doesn't run, which is a critical piece to terminate the call automatically if the user can't pick up the call. We've tried calling the timer in the main queue, but no luck so far.Is there a way to start to timer as soon as app receives VoIP notification and wake up?