他の買い手も同じようなトラブルを経験したそうです。
売主様に、Shipping and paymentsに日本までの送料を設定して頂いたら
送料が表示、加算されて、無事に正常に決済できたそうです。
Shipping and paymentsに日本までの送料を設定してみてください。
お手数をおかけしますが宜しくお願い致します。
The other buyer also experienced the same kind of troubles.
They asked the seller to set the shipping cost to Japan on "Shipping and payments", and the shipping cost was appeared and added, then they could make a payment correctly.
Please set the shipping cost to Japan on "Shipping and payments".
Thank you for your consideration of this matter.