LOST MOST of my stuff after server crash

Game mode: [Online | Singleplayer]
Problem: [Crash | Bug | Performance | Misc]
Region: [Here]
This is the 3rd time the server crashed and when i closed the game and restarted it most of my stuff is gone out 2 of my houses, i been working on steel all day and for nothing. WTF how cant you fix this? TIME WAISTED!!! dayum