My HTC ONE A9 volume slider appears to be half the size it is supposed to be

[Android Admirer 101]

Recently i have noticed that my htc one a9's volume slider sometimes appears to be half (the pull down option to view the music control and alarms control does not appear) or the whole volume slider gets minimized to form a mini volume slider which has the pull down option. Even the easy access apps on the lock screen are larger than usual with a square shaped appearence rather than the shape of the icon. I hope someone can help me with this issue.