This just started happening to me with the new iOS 18.1 update, while playing WoW. The text message will show up on my phone’s lock screen, but will make no sound, and the same happens on my Apple Watch, my Mac also shows no notifications. Some suggestions are to make sure no focus is on (there are none on), and to make sure notification are on (they are). WoW and iOS both updated on the same day on Tuesday, so I’m unsure of which is the culprit. Looked on google and found forum posts for apple dating back to 2016 through 2023, with no solution identified. Some even mentioned turning game mode off, but this is something that literally just started happening on Tuesday after I updated WoW to 11.0.5, iOS to 18.1 with apple intelligence, MacOS to 15.0.1, and WatchOS to 11.1. I hope there is a work around. Some even hypothesized that it could be somehow related to a game mode focus, which I do not have. There is a banner that says game mode is on, and will give higher performance, but turning that off still does not solve it.