Not Receiving The Chest Teward
I just played a game of SR ranked and did pretty well with Braum, so i got an S-. My free chest is ready but i didnt receive it!
Someone got some advice for me?

I just played a game of SR ranked and did pretty well with Braum, so i got an S-. My free chest is ready but i didnt receive it!
Someone got some advice for me?

Tried checking the loot section after closing and reopening the client? I've just completed the teemote mission (for watching VODs) and didn't actually receive the reward until I've relogged. Maybe the drop is choking a bit considering there were some server-side lags and random friend list reconnects lately.
tl;dr try relogging and if that doesn't help, write a support ticket
Edit: are you sure you've got an S grade? It only shows you receiving chest on blitz/garen/WW/darius/sion and not on braum.