When I charge my iPhone 8 in the car, I can't hear it when I use my Bluetooth earphones. It only works when I unplug it from its charge?

When I charge my iPhone 8 in the car, I can't hear it when I use my Bluetooth earphones. It only works when I unplug it from its charge?

The charger port (lightning) is also the audio port.

Go to >Settings, then go to >Bluetooth, then select >Headphones, >Connect