How to install app from TestFlight via itunesconnect as an internal tester in ios?

I want to test application in my device as an internal tester in iTunes Connect. As per new rule to install application through itunes testflight services, I installed new TestFlight native app in my device. And i got one invite as an internal tester.

Now i got one invite to test an application through Email like this,

Now i try to install this app by pressing the button "Open in TestFlight". Now its redirect to AppStore Like This,

Now i press "Open" button, its redirect to testFlight but it doesn't display installation screen of that application. It display like 1 st image i shared in this question.

This is first time am trying to install app from new testFlight. So Please give me some ideas to install app in itunes testFlight.