After the car engine is turned off, the product still does not disconnect from my phone. How can this be resolved?

The product is powered through the vehicle's USB port. On some vehicles, the USB port keeps supplying power after the engine is turned off, which keeps the product running for 3-5 minutes until the vehicle's USB port completely stops supplying power. It is recommended that the customer unplug the product after leaving the car, or turn off the Bluetooth connection.