Kindred passive Bug (GAME BREAKING)

I was playing Kindred and I marked Cassiopia, 2 minutes later I got an assist on her, the mark did not proc and she was deselected; I was prompted right away to mark someone else. To make matters worse, I could not mark her for the rest of the game. If the bug happens multiple times in a match, she could run out of champions to earn her stacks on. Given how reliant Kindred is on her marks, this is a very bag bug to have happen.