[Bug] S-rank but did not receive mastery token for Nexus Blitz

I ended this game with a S rank but there was no mastery token for Irelia granted to me. Any idea why? I checked my inventory just to make sure I didn't just missed the notification. I had two previously and still at 2. https://matchhistory.na.leagueoflegends.com/en/#match-details/NA1/2860001864/38424500?tab=overview