one
The USB driver on your computer is not installed correctly. You can reinstall the USB driver.
two
The driver for iPhone on your computer is not installed correctly or has a problem. You are advised to reinstall it.
three
The USB interface on the computer is loose or the interface is bad, broken, etc., it is recommended to change a good USB port.
four
The cable connecting the mobile phone and the computer is bad, it is recommended to use a good data cable.