My iPhone 13 Mini won't charge either by cable or wireless

My iPhone 13 Mini is in great condition and was working well until yesterday when I plugged it in to charge; it went to a black screen while charging. I thought it was out of power, so I let it recharge for three hours. When I came back, it was completely unresponsive. I then switched to wireless charging and waited for a few hours but again, it was unresponsive. I cleaned out the charging port, then tried plug-in charging again - still the same result. I kept it updated and always used Apple charging cables, so I'm completely flabbergasted as to what the problem is. I'm starting to think that I was sold a unit with a defective charging port. Any suggestions on how to fix the problem? ... I didn't pay so much to have the phone die just two years after purchasing it.