Not addressing your specific issue/question but have you considered using pub.client.sftp:rename instead of get/put? A rename will move a file to another directory. There may be some limitations depending upon the specifics of the SFTP server (e.g. rename that moves a file from one volume to another may not be supported).
For the specific issue, can you share more detail for the get and put calls? There may be a mixing of “contentStream” by using it as both read and write that the underlying services do not like.
#SFTP#webMethods#Flow-and-Java-services