Can't cast any skills when first loading in. [GAMEPLAY]

This has happened to me three times in the last two days. I load into the game and I cannot cast any of my skills unless I click on them with my mouse. None of my bound keys work and if I go into the options to rebind the game doesn't recognize any inputs from my keyboard. The only way I've been able to fix the glitch is by completely shutting down my League client and relaunching. Simply logging out of the match and loading back in from the client doesn't fix it. I don't know what causes it to happen or how to recreate it. So far it seems to be random. I'm not sure how to provide much else for the devs to look over since it's not really something I can capture or screenshot.