Hardware Replacement

I am trying to register for a harware replacement, but get a "somethingWentWrong" error when doin gthe registration. There is no option to mail/call support if I do not have a registered call and this is what fails. So I am in a deadlock. My problem is as follows:

My switch does not transfer traffic anymore. The loop test works fine and when connecting a network cable to 2 consecutive ports both lights at both ends light up. However, the switch does not pass any traffic anymore.
I have tested this with multiple cables, tested the cables themselves as well, used various laptop and desktop systems but nothing works.
The 100M light of the connected computer turns on solid green after a period or blinks now and then, but the lights at the cable connected to my router are dark. Even when I use other ports on the switch. The system receives a self-assigned IP address due to the fact that it cannot find my DHCP server.

How do I register a call? Can anyone help me who has had the same problem?