<Result> <MessageID>2</MessageID> <ResultCode>Error</ResultCode> <ResultMessageCode>18028</ResultMessageCode> <ResultDescription>7124385838040に一致する注文は出荷できません。</ResultDescription> <AdditionalInfo> <AmazonOrderID>503-3391551-1373410</AmazonOrderID> </AdditionalInfo> </Result>
When I used google translate this is the translated text:
Orders matching with cannot be shipped
My only guess based on the information you provided you may have the wrong marketplace id.