Moving house, need permission for installation

I'm trying to move to a new flat. Virgin have asked for my landlord's contract details to get permission for an installation. They never contacted the landlord so I contacted them again and now they say I need to give them the contract details of all of the owners in the building because the flat is on the 2nd floor.

I do not have those details and I don't have a way of getting those details. So they are claiming they can't do the installation. But they are also claiming that I have to pay cancellation fees since the property is serviceable. I cannot afford £400. This is unreasonable. What can I do?