CPU used big bomb and after killing me it killed her as well and was stuck on gray screen before showing defeat. I'm guessing it went on a loop since their is no "draw". Picture can't be uploaded but I can send it via email if necessary.
I got something like that in a 2v2 match, with Peacock, after i used her blockbuster with giant bomb, it killed me with my opponent and i got new fighter from my team and match didnt ended, so i had to restart game
Something similar happened to me yesterday. Fighting the vampire Filia I killed her and also myself at the same time to stall at the grey screen with both champs knocked out. The music was still playing, but i had to quit to reset the game. Using iPhone 6 with the latest iOS 11 update.
Also, most importantly my progress was not saved after I restarted and I had to try the fight again.