Feeling tingly or getting mild shock while charging my iPhone 11.

I just bought the iPhone 11 a few days ago.My phone’s 18W fast charging supported and I use a 2 pin 20W Apple fast charger.But the problem is,whenever I touch my phone’s metal part while it’s charging,I feel tingly or some kind of electricity passing through my hand.Sometimes it increases and sometimes it can’t be felt.Is it normal?If it’s not,what do you guys think the problem is?Please help me if you can!Should I change the adapter or the cable or there’s an issue with my device?