I have had this Minecraft realm classic sized map for pvp and i have built many things on it. and every so often the map will shrink the borders and all my hard work will disappear....

this has been a minor issue until literally half of the map disappeared last night right before we were ready to hold our first pvp tournament!! 

I am very upset with this. 

Don't know what to attach... so i just attached the points that it cropped off the map!