"Maokai" bug that won't let him flash

The video of the match does not really help but I played a game of lethal tempo Maokai in One for All and ran hexflash. My items were BORK and Merc treads.

So I used flash sometime during the game and later on while it is coming back up I used my W on my opponent and flash came up mid W and as i landed on the enemy the flash icon did a little CD refresh like hexflash would if it was coming back up in 10 seconds and was unable to be used for the rest of the match. I tried changing key bindings, clicking, and even restarting the game.

I did provide a screenshot of the Icon being grayed out.

Edit: I put Maokai in quotes in the title because I do not know if his ability caused it or if other champs can reproduce the same bug.