Hi,  Yes, it is necessary.  The attachment is linked via  incomingAccountingDocumentAttachment_create Be aware we are working on a new service to handle attachments, so the API for uploading attachments will change as well. ETA autumn/winter.  Also nota that the example above uses a deprecated method for suggesting values. The new is found here.  ... View more

Thanks @omelhus 🕺 ... View more