Minecraft changes don't save

This is related to my other issues about my villager problem and my chunk problem. After my chunk problem occurs, I log out of the game and log back in. When I do so, I'm in the same area I've been in for a while due to issues, but the whole wall and door of the room has re-loaded and there is still a villager standing in the doorway. I have demolished this wall several times in order to leave the room and saved the changes, but the changes have not displayed.