"Siri won’t change songs in car: [...]It’s not connected via Bluetooth but a cable. Up until yesterday it worked. I updated last night and now it doesn’t. I have updated the Spotify app. Closed all the apps in my phone and turned my phone off and back on. "
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It may be an Issues with CarPlay:
Hardware Issues from Using USB for CarPlay:
There will be nothing damaged in the iOS by using a hardwired connection. I would recommend using rough type of cover for the USB cable --one that is fabric.
For reference...
Troubleshooting CarPlay:
A. Usual Manual:
Read your driver's manual to find out more about syncing this.
B. Try being in Park:
For many, they must have their automobile in park to get this to all pair.
C. Visit this Link:
If you need help with CarPlay - Apple Support