USB charging problem

I try to post here to ask if there is a sort of debugging/logging way to find the origin of my problem.
When connected to the USB cable, the charging icon starts blinking as if the cable is connected and disconnected continuously. In this condition the phone is not charging, but will discharge very quickly. It’s also difficult to connect to your computer to update or sync because it’s difficult to establish a stable usb connection. This problem does not occur when the charging is done via the magnetic connector. This is the second Sony Xperia Z2 with this problem. The first has been replaced by Sony as a defect under warranty, but without success, the same problem occurred after a few days of use. I observed that the issue is started again after after using the magnetic charger . I've also tried to reset the phone and make a full recovery but the issue remain.
I would like to understand if it's an Hardaware related problem or is a software bug.
Here is the link to the video that show the issue https://www.youtube.com/watch?v=Bhv3waE3c0M

Thanks