When I logged on to my world a 16 by 16 by 16 area went from part of my house to being 100 % empty

When I logged on to my world a 16 by 16 by 16 area (that was normally last to load in when getting onto this world) went from part of my house to being 100 % empty (witch included 4 of my chests and some book cases that were part of my enchantment table set up) oh ya and 2 chests within this area became invisible but I could still open them (kinda pissed) (I lost an extensive amount of ores, ingots, diamonds, and emeralds.)

(going to 6 week sleep away camp tomorrow so won't be able to follow up soon)