Silent Push Notifications for Apple devices

Platform, device version and operating system:
iOS and iPadOS, multiple new iPhone and iPad models for at least a year.

Screenshot or image:

What you were expecting to happen, and what actually happened:
I have push notifications set up on multiple Apple devices. Push notifications come in when expected, but they arrive silently. This means no sound or vibration, and therefore no alert sent to my Apple Watch either. In order for me to see the notification, I have to get lucky and check my device. This has been happening for as long as I can remember I just haven’t been bothered to submit a report. Yes, my Notification settings in my iOS settings have Sound and all other sliders and checkboxes on. No other application that I use fails to play sound when it’s enabled. Gems of War is the only one.

How often does this happen? When did it begin happening?
100% of push notifications I receive on an iPhone or iPad. Happening as long as I can remember. I have never received a sound for a GoW push notification on iOS or iPadOS. Makes me think a param or something in code isn’t provided to apply a sound to an iOS push notification.

Steps to make it happen again
Self explanatory. New or existing account. Enable notifications in-game. Make sure iOS notification settings have Sounds and everything else checked or on. Happens on iPhones and iPads running the latest iOS or iPadOS version for at least a year.