Official Response (better late than never)
Hi Edward,
Thank you for contacting Merchant Technical Services.
I am sorry to inform you that our system has been experiencing trouble on passing the shipping fee which is not working properly previously for about 24 hours. However, this has been fixed on our side and it will not affect any future payment from now on. I apologize for the inconvenience caused.
Let me know if you still have any issue.
Thank you.
Sincerely,
Louis
Merchant Technical Support
PayPal, an eBay Company