Once the DTE has been issued when the status of the DTE has not yet been checked, only the stamp and barcode of the DTE will be displayed in the ticket format, when the status of the DTE has been checked and it is accepted, the stamp and barcode will be displayed when viewing the document in the valued format.
If the DTE is shown as accepted and you do not see the stamp and code you must check the document template, from: Settings > My company > My templates.
Enter the document template and in the DTE tab verify that you have the "Barcode" and "Electronic invoice stamp" quadrants checked.