It happend to me too, never with fridge but mostly when I order dyes for fabricator or if I want to travel somewhere by the phone, always when speed of my game is fast. I didnt know for first how to save my progression so I had to quit the game and when I came back so my save it never happend again in same situations.I was quite desperate about my lost progression so if anybody has same problem - I click on windows key on keyboard, then click down with right mouse bottom on icon of Sims game and click on "close window". Window is not closed for real, I go back to game and it will automatically ask me if I want to just quit or if I want to quit and save the game. I know it is not solution for problem here but at least you can save your progression, so it might help somebody.
This actually works on with Alt + F4, then the save window also appears. ^^
