Post the details of your contract.

So it is THEIR physical server. Post the details of your lease. I bet they get to have access how and when they wish, since it is their physical hardware. You say you have an unmanaged plan, yet you want them to help you fix your problems. Doesn't work that way. You say they found an issue with your NIC. Did they change it out? Did you ask them to?

Bottom line ... stop whining and post ALL the information.