iPhone not connecting to computer
So my iPhone 7, completely up to date, is having trouble connecting to my (brand new) MacBook Pro 15inch with touch bar. I am trying to connect it using three different USB cables (all from apple) through the dongle (also brand new) and two of the cables don't register anything, while the third (and the newest) cable prompts the notification that a usb accessory is using too much power thus the port is now disabled. However, having tried with my boyfriend's phone, which is much older and much more beat up, I have encountered no issue. And yet, my phone will charge in my car and with the apple USB cables no problem. So I have now a few questions:
It cannot be the cables because they work with other iPhones
It cannot be my phone because it works with other USB cables
It cannot by my computer or dongle because those are brand spankin new.
So what is causing 2/3 of the cables to not elicit any connection with my phone, and why is the other 1/3 prompting the "USB accessories disabled" notification?
Thanks in advance!
iPhone 7, iOS 11.3.1