Ok, as your friend is also connected via UPC and it works for him, then there’s no general block of this port. I would have been surprised if that were so.
Do you use an own router with the UPC Modem in bridge? Or is your modem in the router mode?
If so I would recommend a factory reset for the UPC Modem by pressing the reset button on the back for 20s. After 20 minutes or so you should be back online. Give it another try.
You’ll loose all your setting on the modem if you do so!