There is an issue with the USB controller on a certain batch of RFSoC 4x2 boards. You should contact the board manufacturer (contact@realdigital.org) to determine if this is the issue with your board.
I have another board, and it doesn’t have this problem. When I connect it to the PC, it shows one new port. I was wondering how I can add the board to Vivado’s hardware manager. Is it even possible to debug my IP cores using the USB port?