最新的iTunes连接版本未在TestFlight中显示

I distributed the first build version of my app to internal testers with iTunes Connect and successfully installed on internal tester's devices. Now, I've uploaded the second build via iTunes Connect. My internal testers have received the email that build 2 is available and clicked on the button to view it in TestFlight, but when TestFlight opens only build 1 shows available to install.I distributed the first build version of my app