Hi VintageAlex,
I am having the same issue and it is so frustrating! I have done all the fixes I could find. Here's the list:
- my sound notifications are on (flip switch on the side of the phone)
- do not disturb is off
- under settings/notification/Instagram, my Instagram notifications are set to allow, all three alerts are checked, temporary banner style, sounds and badges are on
- under Instagram notifications from within the app itself, all push notifications are on but in particularly, the live videos are on and those are the ones I am most interested in
- I updated my software to the latest iOS15.4
- I deleted the Instagram app and reinstalled it to be the latest 226.0
- under sound and haptics, I have vibrate on ring and vibrate on silent turned on, ringer and alerts turned all the way up, system haptics turned on
- I reset all settings on the phone itself
- I reset the Network Settings
- I confirmed that Low Data Mode and Low Power Mode are both off
- I confirmed that Background Refresh is on for Instagram
I believe this is some type of issue b/w iOS 15 and Instagram and Probably will not be resolved until Instagram updates their software to fix it. I reported the problem to Instagram, but there seems to be no way to get one-on-one help from Meta.
So as far as I can tell, we are left with no option (other than to check our phone every five minutes) until Instagram gets its act together and starts playing nicer with Apple. It's entirely frustrating because every other app I am getting sound notifications for: Facebook messenger, discord, iMessages, Facebook. It's only Instagram that is causing problems, and like you, I initially had sound for them but now no matter what I do I cannot get it back.