Hey Rio,
As @guardian10 said, your phone is likely toast.
I'm a little sus about the part you say you use the original 5W charger and a USB-C cable as last I checked, those use USB-A not C.
If you can argue enough with Apple they might replace that phone but if they charge you an absurd amount then SOL. On the flip side if ur into microsoldering, you can use this phone as parts.
***Beware of Apple's tricks of trying to get you to buy a new device***
Here's a story of mine: I have an Apple watch SE that had software issues so i did the usual. I also had a 4 that was stuck in an infinite boot loop and this specific support person fixed it. Not even the Apple store could do that! Try using Apple support online first so your not screwed over by the Apple store (I don't want to name and shame the specific one as that is just inexcusable so I'll leave it at this)