Something doesn’t seem right. What sort of container are you using to mix your lye solution? A full ounce is a lot to come up short. I once made a layered soap using the same method and came up short by a few grams for the last lye solution pour, but it was because the container I was using had some nooks and crannies. But a full ounce? It is highly unlikely that you’re losing a full ounce from evaporation.
