Game crashes randomly

My game crashes randomly when I'm playing, especially when I fly with an elytra. Most of the time it's just a little inconvenience. This time it was different. I was gliding in the end out of fireworks about to land on the island when one of these crashes happened. It was very sad as I lost all my stuff. I changed it to creative, then got all my stuff back with the exact enchants. Is there anything u can do to re-enable achievements in my world?