Hello,

First, let me say that I'm not sure if I've reported this correctly but, I'm going to try breaking this down in hopes it helps explain the issues.

Firstly, I've been playing split-screen Minecraft with my sister on her Xbox One for a week with no issues till today. She signs in first to access the world so we can play together and I join using the same second player controller and signing into my Xbox account. She usually saves and quits the world which kicks us both off at the same time and subsequently saves both our progress. Today though I logged in same as usual and have had my progress reset (at spawn, new skin, empty inventory, no levels). So, I figured that somehow my world profile wasn't saved so I tried playing for a bit and before getting off this time I saved and quit first. Coming back I log in and the same thing has happened my progress has been wiped and my character skin changed to default again. I've tried this a couple of other times and even tried turning off the Xbox and back on which seemingly helped but after leaving the game and coming back the issue persisted. 

Secondly, another problem we've been having is a severe lack of diamonds and emeralds in the world. I've explored an entire map (upgraded 4/4) chunk which had multiple villages, desert temples, an ender fortress with no end portal and found a handful of emeralds but NO diamonds or equipment in any chests. We've also started a strip mine at height level 12 which covered a vast amount of land and countless caves and caverns and still no diamonds or emeralds. I found three minable diamonds at height level 16 once but that was all. So, in this regard, I think we just got a bad world seed. The first issue is the biggest and most important but I'm hoping that the second issue might have a solution so we don't have to throw away a weeks worth of gameplay.

In summary, any time I come into the world as player two and leave either manually saving myself or not my character is reset and the world we are playing has a very noticeable and severe lack of diamonds and emeralds which I believe can just be explained as a bad world seed.