The USB port in /older) cars and attached to radio etc. are installed there primarily for the sake of data transfer (like playing music from your phone or player into the car sound system). Beyond that, nowadays, they usually also give out a charge to a connected phone, but it's a dreary process seeing how the output is weak/slow. And no, the output here isn't about voltage, it's about low amperes.
Also the infotainment of your car may, over time or even from the beginning, fail to recognize your phone (that's not uncommon, especially with older model cars).
Have you checked whether yours works with the phone to play music into the system? If it does then you're one headache short in that a charging adapter that goes into your cigarette lighter socket, better said 12V power outlet (USB port at the other side) gives you a better charging performance anyway.
Of course I also recommend following the advice of others here of checking the fuses.
Just FYI my car (model 2020) has a radio with a USB port that also gives out a charge, but I use that port only to pipe in music from a thumbdrive. Seeing how it also has a bluetooth function, I don't need to plug my phone into it at all (and never do), but prefer to charge it via the above method for far better performance.
Even with more modern radio USB systems you're more likely to drain your phone battery (while in playback) more with syncing than you're actually getting out of that socket as a charge.