Summoner spells not casting correctly (GAMEPLAY)

Occasionally when I try to cast a summoner spell It will not cast immediately or at all, I have done this on Twisted treeline and Summoners Rift.

To reproduce 1)Go into hotkeys settings and hit "Restore Defaults" Hit okay 2)Hit "Quick Cast all" 3) Tick on "Replace Quick Cast with Quick Cast with indicator in quickbind UI" 4)Issue a Command (Walking, attacking, cast a spell etc) 5)Hold Spacebar so the camera is on your champion 6)Attempt to cast either Flash,Ghost, Or Ignite

I can successfully reproduce this bug (although not every time) with this method