statcast_single_game Only works after game has concluded.

As my title states, I can only pull data after the game has concluded. I'd like to view this data as the game is progressing along..

Here is a snippet of my code:
```
def getSingleGameStatCastData( gamePK ):

singleGameStatCastData = statcast_single_game(gamePK)

return singleGameStatCastData

GAMEPK = 778279

# get all the statcast data for given game ( game_pk )
hittinData = common_subs.getSingleGameStatCastData(GAMEPK)
```
I get the following error:
TypeError: 'NoneType' object is not subscriptable