Upon arrival, the customer directed us to the guest bathroom, where the toilet was continuously running. After a thorough inspection, we determined that the flapper was warped, preventing the toilet from properly filling. The fill valve was found to be in excellent condition and did not require replacement. We provided the customer with an estimate for replacing the flapper, as this was the primary issue. Following approval, we proceeded to replace the old, warped flapper with a new Korky universal flapper. After installation, we tested the toilet by filling it multiple times to ensure proper function and resolve the running issue. The toilet was fully operational, with no further issues detected.