Hi lloydfromvalentine,
Restarting your iPhone will refresh iOS, which may help with this issue. If you're unable to restart it normally and it's unresponsive, force restarting it could get it up and running again. Here's how: Force restart iPhone.
1. Press and quickly release the volume up button.
2. Press and quickly release the volume down button.
3. Press and hold the side button.
4. When the Apple logo appears, release the side button.
If your Mac isn't recognizing your iPhone, this resource will guide you through some helpful steps: If your computer doesn't recognize your iPhone or iPad.
If the issue persists, reach out to Apple Support directly so they can look into this with you further. They can be contacted here: Contact Apple Support or by calling the most applicable phone number from this list: Contact Apple for support and service.
Regards.