【発送方法を間違えてしまった（当店側ミス）】

謝罪し、送料差額を返金しましょう

(例)
We are very sorry that our shipping department has mistakenly shipped your item by
Registered shipment which is not as fast as EMS.
It takes about 2 weeks~ 1 month for delivery but has tracking.

We sincerely apologize for this trouble and will improve our service much more and promise that it will never happen again.

Please accept our apology and refund for the overpaid shipping cost.

⇒【返金方法】 を参照ください

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