I don’t know-I’ve had that happen when I overfilled a pan-but I’m bad about doing that-I’ve even had loaves of bread get out of hand in the oven. Did the recipe say how much to fill the container? Most of the time, it really doesn’t, so you have to guess at it...
I will use deep dish pans next time and cut the salt at least in half. It is way too salty for me and I think it would not be good to give to my elderly friends so I’m baking them a coffee cake instead. It is called a salted caramel pineapple upside down cake but apparently salted caramel anything is too salty for me.