My two sims are making cupcakes for their small business and I noticed my male sim saying he couldn't continue an action. When he stopped cooking the cupcakes my female sim stoped baking her bread and proceeded to pick up the bowl of her partner and finished his dish.
to be sure, you didn't use join cooking but each cooked their own meal ? Do you have more than one oven ? There can be conflicts if two Sims want to use the same object at the same time.
I used two separate cooking actions and I had two ovens and two fridges. One was cooking cupcakes the other bread.
Here are some pictures I got of it happening after I replicated it. in order of the steps and I Clicked cook separately
I'm going to put this on review for Maxis to decide if it's a bug or not I personally don't think it is. The game has many instances where if you tell it to do something on an object it can decide to use a different one and if two Sims use the same objects, the interactions cancels.
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