fall down on
Drop the ball
To fall down on something is to fail at it or neglect it, especially a duty or responsibility: He's been falling down on the job lately.
The phrase suggests stumbling or collapsing where you should have stayed upright—a vivid image of inadequacy where competence was expected.
neglect
Failure to provide care
fumble · flounder · mishandle · underperform · drop the ball · slack off · let slide · mismanage · default · flub
effort and commitment
fall down oncome through
Fulfill when needed
step up to · rise to the occasion · see through · stick with · keep up with
fall, down, fell, fallen, falling, falls, downtown, downpour, downward