Your description is unfortunately not detailed enough for me to advise you properly. A photo of your hair (which you can upload with your answer) would have been great in this instance.
If this bald patch is isolated, it may be alopecia areata. There is a simple treatment consisting of an injection for this – you can visit NSC to receive treatment. Or otherwise all dermatologists/some doctors do this too.
Your description of short thin white hair sounds like “vellus hair”, which can appear in male pattern hair loss.
Treatment for this is a topical shampoo minoxidil, an anti-testosterone drug called finasteride (which can cause side effects), or hair transplant which is kinda expensive. Vellus hair MAY turn into darker thicker hair, but because they appear as a sign of male pattern hair loss, I advise you to consult a doctor in person to have it properly checked out.
You can read this article for more information about hair loss treatment in Singapore.