Fiora not being able to use summoner spells.

I am a fiora main and i have experienced this in about 40% of my matches in the recent times its when you recall back to base and buy something form the shop and when i try and put my camera to my tower to teleport to it when i realise that i cant teleport it is grey'd out the same with flash this make me have to walk back to lane whenever this happens and the spells do not become available again until about 2 minutes after getting back to lane. So i think this is a big thing and it is only with fiora i have spoken to other fiora players and even they have experienced it too and i hope you could get this resolved soon - SGkieran