This is a post that I have been meaning to write for a number of days now but given that I've been busy working on the site, I haven't had a chance to publish anything.
There a numerous reports online that following what I believe was the Springfield Heights update, a large number of players reported losing some, most or even all of their doughnuts.
This is apparently due to a bug that I am somewhat happy to tell you that the EA devs are aware of the issue and are actively working to fix the problem.
In the meantime if you contact a game adviser they should be able to credit you the missing doughnuts, once you've explained your situation and tell them how many doughnuts you're missing.
You can contact a game adviser using the 'Contact EA' tab in the menu above.