Has anyone ever had a fully cured bar of soap that was just fine and had a good lather, suddenly stop lathering? I made some lavender soap last year and I gave a bar to my sister at Christmas time. She's been using it for the last month and she said it was lathering just fine when she started using it but suddenly it just stopped producing lather. She tried using a poof and nothing. She said it still cleans and feels nice but there's absolutely no lather. It's the same recipe I always use and none of my other soap has shown any issues like this as far as I can tell. I haven't used the lavender batches though because I don't like lavender.