Got it, more info...
it's highly likely they were beyond their expiration, I've had the exact same thing happen to me, so learned by experience not to buy them any longer if they don't bear a *readable by humans!* expiration date. None of that number/letter code nonsense manufacturer's love to use on us! Even then, after I open them, I check each one to make sure they're firm - and - they really need to be used within a few days of opening a jar (at most, a week). If you're near a Trader Joe's the fire roasted frozen chestnuts are a good substitute, and are individually frozen so you can remove just a few from the bag at a time. Skip entirely the chestnuts in water in a can, they seem to be an expensive joke, though the sweetened & unsweetened chestnut purees (canned or, better yet, in a squeeze tube like toothpaste) are very reliable. I use those often but primarily for making desserts and filling chocolates.
Good luck!