Hi Dan, I think I already have a clearer understanding of how the reports work thanks to your message. The URL I sent you seems to be not correct, this is the valid one
http://archivo.plasencia.es/index.php/Ayuntamiento-de-plasencia/reports in case you want to see it.
As we have created the funds, we are going to have to make modifications since instead of assigning simple or compound documentary units, we have assigned other levels of description. Your colleague Nacho has guided me on how to solve it and surely we will do so.
Thank you as always for your time, greetings.