Query EntityFramework

I changed the codes from the previous question, to use a string that makes things easier for me. I got what I was looking for. Now what is generated is the following exception:

System.InvalidOperationException: 'The entity type ProvidusCuotas is not part of the model for the current context.'

Controller:

public ActionResult Index(){
            SQL sql = new SQL();
            List<ProvidusCuotas> lista = sql.cargarDatos();
            return View(lista);
        }
        public ActionResult PrintViewToPdf(){
            var report = new ActionAsImage("Index");
            return report;
        }

public ActionResult PrintPartialViewToPdf(string id){
            using (PDFPrinter db = new PDFPrinter()) {
                ProvidusCuotas customer = db.SQLs.FirstOrDefault(c => c.titulo == id); //justo en esta línea se genera la excepción
                List<ProvidusCuotas> lista = new List<ProvidusCuotas>();
                lista.Add(customer);
                var report = new PartialViewAsPdf("Detalle", lista);
                return report;
            }
        }

SQL class:

public List<ProvidusCuotas> cargarDatos(){
            List<ProvidusCuotas> salida = new List<ProvidusCuotas>();
            SqlConnection conn = new SqlConnection("conexion");
            conn.Open();
            SqlCommand comand = new SqlCommand("SELECT titulo, apellido +', '+nombre,max(Cuota) FROM V_CuetaWeb GROUP BY titulo, apellido, nombre ORDER BY titulo ASC", conn);
            SqlDataReader dr = comand.ExecuteReader();
            while (dr.Read()){
                string titulo = Convert.ToString(dr.GetDouble(0));
                string nombre = dr.GetString(1);
                string cuota = Convert.ToString(dr.GetDouble(2));
                ProvidusCuotas p = new ProvidusCuotas(titulo,nombre, cuota);
                salida.Add(p);
            }
            conn.Close();
            return salida;
        }

PDFPrinter class:

public partial class PDFPrinter : DbContext
    {
        public PDFPrinter()
            : base("name=PDFPrinter")
        {
        }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            throw new UnintentionalCodeFirstException();
        }

        //public virtual DbSet<V_CuetaWeb> V_CuetaWeb { get; set; }

        public virtual DbSet<ProvidusCuotas> SQLs { get; set; }
    }

The problem arises when in the INDEX I click on this link:

            <td>
                @Html.ActionLink("Azul","PrintPartialViewToPdf", new { id = item.titulo})
            </td>

The idea is that when clicking on that link, a pdf is loaded with the information I need but the exception mentioned above arises