iPhone 12 Pro Max electric shock

I have a IPhone 12 Pro Max and have it charging next to my bed and use it while it’s charging. Sometimes I have it faceing upward in my chest when reaching for something or getting something. Only when i was shirtless I starting getting these stings or pinches from my phone. At first I thought the case had pinched me or something but I soon realised after it happening regularly that the metal and silver lining around my bottom left camera was the thing giving me a slight electric shock. I even checked to see if I was imagining it but there it was and I saw it happen. Not sure if it’s a fault issue or an issue with the voltage from my house etc etc im not an expert but it’s definitely happening when im charging my phone and using it at the same time. Not sure where to go from here