Chunks won't load.

Around 4 months ago, I created a bank in Minecraft, I spent a lot of time and effort on it and suddenly I logged in and when I went up to the build right where the chunks would only load where there was land, but where the bank was, there was nothing! The chunks wouldn't load so I tried reloading and when I saved and exited the loading screen would just stay on forever unless you force quit the game. When I tried going on again, the same happened. I tried all chunk loading commands and none worked. Please fix this glitch, I'd like to have my hard worked on bank back. Thank you. Minecraft Username: Riley_3124