The issue should be resolved now. You will likely need to restart your game and it should download an update. Please let me know if they show up correctly now or if they're still missing.
https://forum.paradoxplaza.com/forum/forums/support-bug-reports.879/
Depending on your operating system the log can be found here:
Windows
\SteamApps\common\Cities_Skylines\Cities_Data\output_log.txt
\CitiesSkylines\Cities_Data\output_log.txt
Mac OS X
~/Library/Logs/Unity/Player.log
Linux
~/.config/unity3d/Colossal Order/Cities: Skylines/Player.log