You will not be able to transfer files from a storage device to Jio Phone when you get the handset via the USB cable because the option is turned off by default. To enable it, go to the Storage tab under Settings and select the USB Storage option. Here, simply select the Enable option and you will be able to transfer files using a USB cable. However, if you have set a passcode lock on the phone, you will have to unlock the phone to transfer the files as the phone will not appear in the list of devices on your phone otherwise.