The issue is that the game cannot read the save file located inside the game's save data folder inside your documents/telltale games folder.
To fix this, hit windows + r and type

C:\Users\%USERNAME%\Documents\Telltale Games\Poker Night at the Inventory
or
C:\Users\%USERNAME%\OneDrive\Documents\Telltale Games\Poker Night at the Inventory
Then delete the save file that's in there (default is called pnati_save.save)

Afterwards the game should start correctly.

Enjoy!