Charging my iPhone in my car

In that case, it sounds very much like the USB port failed. You may want to take it into your local Audi dealership, and have them check out the port in the head unit.

Sounds like it developed an issue, and it no longer charges the phone nor enables CarPlay.

What Audi model and year is this?

Does it actually support CarPlay?

In regards to charging, when the iPhone is connected to the USB port, and the car is turned on, the battery icon should turn green, to signify its charging. If this does not happen, then USB port may not be providing enough power to charge the iPhone. If there's another port try it out. Most cars will not provide power through the USB ports when they are turned off or in stand by mode, with just the radio or head unit turned on.

The talking through the system is done over Bluetooth, and would have no connection to charging. If the port is malfunctioning, then Bluetooth would still work.

You really will need to provide more details.

How are you attempting to charge the iPhone in the Audi?

Are using a built in USB port?

Are you using a lighter adapter to USB?

Are you using a wireless charger4 built in to the car?

Something else?

What happens when you attempt to charge?

Are you using the same cable in the car as elsewhere?

Have you tested with a different car?

Please provide details about your issue, and someone may be able to advise.