App Crash in middle of TB

BlackIrish

I was on Phase 4 of 2nd Combat Mission when my sound went dead. Game still worked but sound went kapoot. I pulled down my system menu to access Sound settings. All seemed fine, so I returned to the Game app to find what I will term as a "black screen of death" meaning the game app is clearly open, but all the user can see is a black screen. No sound, no nothing. I left it to sit for a 10-15 seconds and notbing changed. I minimized and maximized the app, let it sit for another 10-15 seconds, still nothing. I then switched from my wifi to my LTE and still no luck. Finally I closed the app. Now the final 3 waves of that battle node are lost.

I have a brand new (barely a month old) Samsung S8+.

Is that experience I just had something that just happens from time to time across devices? Or native to devices running nougat?