Unplug the power cable of your refrigerator.
Pull the plastic frame off the dispenser on the door of the refrigerator.
Lift up the control panel of the dispenser and pull it slightly out of the housing to expose the panel wiring.
Unplug the wiring harness from the rear of the control panel. Remove the control panel and set it aside.
Remove the screws on the corners of the dispenser housing with a Phillips screwdriver. Pull the housing out to remove it. You now have access to the flapper.
Pull the flapper down to unhook it from its connectors and remove it. In many instances, the flapper will have simply become loose and needs to be reattached.
Slide the top of the flapper back into its compartment until it snaps in place. If the flapper is cracked or otherwise broken beyond repair, you can fit a new one in its place instead.
Replace the dispenser housing and screws.
Plug in the controller wiring and fit the controller back into the housing.
Fit the frame back over the dispenser.