getmytrend today whole day we spent in diagnosing the store app, but we were not able to find any issues.
We did some tests as well (by keeping the app in lock screen for 25mins and then creating a new order) the ringer was working fine for us.
We have done some core changes in the notification functionalities today, and all the tests were done after that from our end.
Please check if the app works fine for you now.?
Please make sure the store app is the new Platform store app and not the old store app (both looks identical)