when i click on update button using parameter it shows previous report totalpages

when i click on update buttong by passing parameter i received previous report total page count.

here is my code :

report.params({'startdate': [startdate], 'enddate': [enddate]}).run(function (html) {
                console.log(html);
                alert(html.totalPages);
            });

i need current report total page count.

i also used

report.params({'startdate': [startdate], 'enddate': [enddate]}).run.then(function (html) {
                console.log(html);
                alert(html.totalPages);
            });