The 2 possibilities that come to mind are mods related errors or a misunderstanding of game mechanics. Each day, every person in mansion(including player) has a default consumption of 10 units of food, though this can be reduced by employing a cook.  Workers with Clumsy trait will actually only bring back 70% of this stated value. Otherwise, this mechanic works quite reliably in my experience and I've not heard of any problems.

Though the fact that it says how much food they collected means that the code probably did not have any errors. The effects of mods or other alterations of the code are hard to predict. If you have either, I would need to know what they were to diagnose them.

Edit: For Windows OS, the game opens with 2 windows: the game window and a terminal that will print error messages as they occur.