Losing Inventory upon spawn

Loaded two new survival worlds recently and sank 8 hours into each just for me to log in someday and have absolutely nothing in my inventory. After the first incidence I was told to restart the game but this didn't work the second time and I still have nothing on me. Entered other Survival Worlds I didn't care about and it occurred on every single one I entered. Creative seems to work fine. All items in chests are safe