Flaking or delaminating bags are most often the result of age, heavy use, or improper storage. The most common culprit is storing bags while they’re still damp or in humid environments. Unfortunately, damage caused by these conditions is typically not covered under warranty.
If the interior of your bag is peeling, you can try re-coating it with an aftermarket urethane product like GearAid’s Seam Grip TF. Be sure to follow the manufacturer’s instructions carefully. For best results, remove as much of the old, flaking coating as possible before applying the new treatment. While results may vary, this method can extend the life of your bag.