Tested plugin

src/main/java/nz/jimmy/easyspawn/EasySpawn.java

@@ -26,7 +26,7 @@ public class EasySpawn extends JavaPlugin{
 					float yaw = getConfig().getInt("spawn."+w+".yaw");
 					player.teleport(new Location(world, x, y, z, yaw, pitch));
 					player.sendMessage("You have been teleported to spawn.");
-				} 
+				}else{ player.sendMessage("This world has no spawn");}
 				return true;
 			}
 
@@ -39,6 +39,7 @@ public class EasySpawn extends JavaPlugin{
 				getConfig().set("spawn."+world+".z", location.getBlockZ());
 				getConfig().set("spawn."+world+".pitch", location.getPitch());
 				getConfig().set("spawn."+world+".yaw", location.getYaw());
+				saveConfig();
 				player.sendMessage("Spawn set.");
 				return true;
 			}