Same thing is happening for me too. I would play and all of a sudden a random key of the four (accelerate,brake,left,right) would stop responding completely. The only rescue is to rebind key in game control settings. Then it would happen again to another key. Very frustrating, especially if leading the race.
I would get out of the game and key works outside the game so I doubt it is Windows issue.
Windows 10, latest Chrome browser, Microsoft Surface Bluetooth keyboard.