Hi , I'm David, thanks for participating in the Microsoft Community. I'll do my best to help today.
Try to connect to another USB port or try another cable.
If that does not work, try to uninstall the driver of your cell phone and reinstall it
-Open the Device Manager by right clicking on the start button.
-Select the driver in the device list, then right click on it and press "Uninstall".
-If you are offered the option "Remove driver software from this device" mark it too.
Best Regards,
David.