Hi Gemma Garinga, I'm sorry to know that you dropped your pen in the water. All Huion products come with a 1-year warranty for those purchases made from our authorized online and offline platforms. However, I'm sorry to inform you that man-made damages such as dropping the pen in the water is not covered by the warranty.
You don't have to worry though since you can purchase a pen for your H430P tablet using this link: Huion Battery-free Pen PW201.
HUION Customer Support