I have vanison meat in a single fridge connected to dispenser working and then suddenly stop working (no meals made).

Turns out if one of the three stacks is to small for a meal, the others are not going to be used instead. Its not about mixing ingredient, but using just one from the stack that is large enough.

I had 75x 3x and 75x and I had to order my pawn to take down the 3x in order for the dispenser to start working again. Before it thought it has no ingredients.