My log home was chinked with Permachink about 10 years ago. Soon afterwards, bubbles began appearing. The contractor said they would go away. They didnt. We are soon going to be removing old stain and applying new. Do we pull out old chinking or just don’t worry about bubbles. We also have a few cracks in chinking.
My guess is that the contractor put the wrong backing foam in. If it is not a ”closed cell” foam it will give off gases and cause the bubbling. If it is not broke loose or crack it probably is OK other than the looks. It would be expensive, but the best thing to do would be to remove it and reinstall.