The water in the unit caused the battery to short out and drain. There may still be moisture inside continuing the battery drain. You probably need to open it up and make sure its dry and without corrosion. Then replace the battery if possible. Ralph
+
The water in the unit caused the battery to short out and drain. There may still be moisture inside continuing the battery drain. You probably need to open it up and make sure its dry and without corrosion. Then replace the battery if possible. Since I don't know which version you have I am including the teardown for the second version. Rest assured ifixit has teardowns for all versions. Ralph
The water in the unit caused the battery to short out and drain. There may still be moisture inside continuing the battery drain. You probably need to open it up and make sure its dry and without corrosion. Then replace the battery if possible. Ralph