Items disappearing

This has happened twice. First time I had just finished mining ALL night, I went to sleep then next morning I go to play and my inventory is gone as well as some diamonds & enchantment table that I had in a chest.I proceeded to quit & abandoned that world. I went a fews days with no issues in another world but Today I stopped for a few hrs then I go to play again & I spawn back at the original spawn point & my WHOLE inventory is gone…pls fix this