[CRASH/GAMEPLAY] Client crashes after clicking Hextech button when team-mate got S

I have Hextech chests available, a team-mate receives a S rank (i did not), no chest was granted. Clicked on Hextech icon, client crashes. After re-logging in (and closing previous 'still open' client), I note that my number of available chests had not decreased. Clicking on Hextech icon allows me to enter it no prob. This has happened twice that I've noticed.

1. Have Hextech chests available, note the number available.
2. Play a match. Do not get an S-rank, a team-mate gets a S-rank
3. Observe in post-game lobby that a chest was not granted
4. Click on Hextech crafting, game should crash.
5. Re-enter game, note number of available chests