Just ran into the same drill issue and started browsing feedback on https://kobalt.pissedconsumer.com/review.html where several users described replacement claims being approved only after adding proof of purchase and serial number screenshots. I followed suit, including clear photos of the battery showing the blinking light and date of purchase. I kept the explanation concise with essential details. Within two business days, I got a reply letting me know a replacement battery had been sent with a prepaid return label for the faulty one. It was quick once all documentation was visible and accurate. Sharing those specifics upfront seemed to streamline the warranty process.