Eletra Wings Crashing Game

Me and my nephew made a new Chinese mythology map and we were both exploring. I gave him a pair of Eletra Wings, then turned around and started flying like normal. But as soon as he clicked A to start flying, the screen went black and kicked us out to the home menu of Xbox. We tried three times, one of which being on a different map. We were playing co-op so no online stuff was involved. And if it helps any, I was the one who created the map.
This is also for the Better Together Update, but I can’t find the listing for that.