No "Touch To Return To Call" banner
I have a brand new iPhone XS. When I have an ongoing call, the only way for me to toggle back to the call is by dragging my finger up from the bottom of the screen to find the app and open it, but apparently there should be a green banner on the phone screen that reads "Touch to return to call", however, that banner is not appearing on my phone.
Is this a feature I have to turn on, or could something be wrong with the device? Ty!
iPhone XS, iOS 12