Regarding this issue, I’d contacted to Mail Admin of Kiaceramics.com. We acknowledged that domain kiaceramics has been limit amout of incoming mail for each mail domain because domain kiaceramics.com want to prevent the delivery of spam to the server. When incoming mail from scg.co.th over limit, the remain mail must waiting in queue mail and retry to reach domain kiaceramics.com. However, this issue has been solve by mail admin of kiaceramics.com.
Anyway, Thank you for your kindly support krub.