I just fixed mine that had fell in a creek.
Tried rice and a hair dryer but none of that worked
End up taking it apart to fix it. Found water tracks on the circuit board that were removed by polishing with a micro cloth. To take it apart, remove the red rubber shell. Same with the black. They just peal off. Then you find 3 tiny screws holding the two haves of the white casing together. The white casing will separate and fold apart allowing the guts to be removed. 3 more tiny screws hold the circuit board on. Remove those and inspect the circuit board for water stains. I polished it everything I could reach, even the ribbon cable between the lens and circuit board. Put it back together and it works fine.