This is the normal process:
Once you receive the one that doesn't specify the art. 51, follow these steps.
Go to:
http://www.dnrec.jus.gov.ar/
- Tramites particulares
- Sistema de Gestion e Informacion al usuario
- Reclamos
- Reclamo – Tramitacion
- El tramite no fue entregado con excepcion al art. 51 del Codigo Penal
Enter your information and then you will be able to attach documents.
You must include a signed letter requesting the art. 51, with a copy of your national identity document.
The letter should say something like “Requiero que el tramite indique que es emitido con excepcion al art.51 del Codigo Penal”, include your full name, signature and national identification number.
I think you have a maximum of 30 days since you get it to request this change. They were very quick responding back with the new one: 1 day or so.