Why is my text box changing its position when I am replying to a message (iPhone 6 Plus)?

keyboard is go nearer to the text box from bottom and it shows till T only. i think it goes to landscape keyboard.

Restart the device... if you still have issues, connect to iTunes and restore the iOS...

Hi thanks, i restored it two times again i am facing the same issue. and today i restored it with 8.1.3 and then also facing the same issue. i got this twice/thrice a day. i almost sending 100 msg/day