How do I get my iphone to connect to Itunes with USB cable ( Mac ) ??

My iphone has not been able to connect to the mac for around a year now by USB, but it can over wifi though.

Fault finding steps:

I have a new original cable & tried others to no avail, all software is up to date. I have done the "option, System Information, USB" but it does not show the iphone 6..

I have done a hard reset on the phone, reset the computer too.

Any ideas you have would be appreciated.