I investigated your city and all of your walls looked complete. The pictures you showed also shows them complete. Remember that there will be three out posts outside of your city. Please confirm if you are still having issues or not and if you are please be more specific which part of the map. Thank you.
If I always appear prepared, it is because before entering on an undertaking, I have meditated for long and foreseen what may occur.
--Napoleon Bonaparte, 1831