After receiving the goods, the customer complained that there was no problem with the first use. However, during the second use, the pin became loose (if the core rod is not used correctly, it may also become loose or break due to reaction force). We actively requested the customer to send us pictures of the damage for review. If it is our fault, I will actively cooperate in handling it and also send a refund. However, the customer has not responded positively to us and expressed deep regret before leaving a review of our product.