Viktor Skill Level-Up/Upgrade Bug [GAMEPLAY]

When I purchase a core upgrade in ARAM (haven't tried in other game modes) after dying, if I have a level up available, after I choose which ability to upgrade from the core purchase, I am unable to level up my abilities. Empty golden boxes appear above the abilities but there is no way to click them to level anything up. I waited for until I had three levels saved and nothing changed. Buying the next core upgrade also did not fix it. I had to exit the game and reconnect in order to level up the abilities. This happened in two different games with Viktor, so it should be easily replicated.