Why can't I continue my campaign in Tropico 4?

I completed mission 4,5, and 6 in Tropico 4 and saved the game and quit. When I went to continue my campaign I went to the main menu and Campaign options, but most recent mission available was mission 4.



I could reload my save game and continue mission 7 that way, but I'd like to know why my mission progress isn't saving in the mission selection screen so I can go back and retry missions later.



I tried completing mission 4 again today just to see if that would unlock mission 5 from the campaign menu and it did not.Why can't I continue my campaign in Tropico 4?
You should patch your game, it happened to me too, if it does not help, while playing the game type these letters on the keyboard e l p o l l o d i a b l o or elpollodiablo, it will skip a level and you should complete it.