iPhone 11 iPhone 11 calls don’t work in car with AUX Jack.

[RayA1985]

I recently acquired an IPhone 11, and I bought an AUX Jack so I can both charge the phone and listen to music at the same time in my car. This works fine. However, I am unable to hear phone calls over the car speakers, as I had done before when I had my IPhone 6. I am currently running 13.3.1 IOS. I believe it’s a software issue, and does anyone else have this problem? And have you found a fix? Thanks.