API OData does not show values

Use VS 2017, I made a web service following a tutorial, but when executing it, it does not bring anything from the database and instead shows:

<ArrayOfstring>

value1 value2

public class ClienteController : ApiController        
    {
        private bd_banco_cesdeEntities db = new bd_banco_cesdeEntities();
        // GET: api/Cliente
        public IEnumerable<tbl_cliente> Get()
        {
            return db.tbl_cliente.ToList();
        }

The model

public partial class tbl_cliente
    {
        public int DocIdent { get; set; }
        public string Nombre { get; set; }
        public string Apellido { get; set; }
        public string Direccion { get; set; }
        public string Telefono { get; set; }
        public string Estado { get; set; }
        public System.DateTime FechaIngreso { get; set; }
        public string Password { get; set; }
    }