Apologies for replying this late, things been starting to get busy for me as the world starting to opens up. I’m happy to report that the symptoms are gone for the past couple of weeks. I consulted with my bike fitter and she told me to adjust the hood a little bit inwards and handle bar a little bit downwards, after some trial and error, the symptoms disappear. I have ride up to 35km or 90 minutes without any symptoms. Still on the way to build up my stamina and see if any symptoms appear on longer ride. But so far so good.
According to her, I rested my palm too much on the handle bar thus the pressure on the resting affect my nerve. Probably a pinched nerve.
Last but not least, Thank you very much for everyone for your kind advice.