Plugin admin Unable to upload file : Bad filename

admin

#1

I have one list field inside another list field and I have problems upload images via admin in the second list field always give me this error Unable to upload file : Bad filename

I have this blueprint for this page:

title: GDA Blueprint
'@extends':
  type: default
  context: blueprints://pages

form:
  fields:
    tabs:
      type: tabs
      active: 1
      fields:
        content:
          type: tab
          fields:
            header.direcciones:
              name: direccion
              label: 'Direcciones'
              type: list
              style: vertical
              fields:
                .nombredireccion:
                  type: text
                  label: 'Nombre dirección'
                .links:
                  label: 'Links'
                  name: links
                  type: list
                  style: vertical
                  fields:
                    .linkname:
                      type: text
                      label: 'Nombre'
                    .img:
                      type: file
                      label: 'Imagen'
                      destination: 'user/themes/gda/uploads/marcas'
                      accept:
                        - image/*
                    .linkurl:
                      type: text
                      label: 'Url'

Can anyone help me?