Inspect the shell of the device before placing the button pad and center toggle back into the device.

Look for cracks in the device's shell and identify whether the device shell is obstructing the button connection.

Clean the shell thoroughly using a cotton swab into the creases of the the device shell. Use a water dampened cloth to wipe down the device shell inside and out.

The center toggle (circled in red) button snaps into place. Be sure the center button is placed in correctly.