Hi @Anonymous User
Bit of a long shot have you already plugged in the NOW Hub Router (assuming there is a telephone line and BT master socket in your home) just in case the BT Openreach Engineer got everything working at the street cabinet and after testing didn't need access to your home.
I have seen this in the past where the Engineer didn't have the courtesy to phone the customer or knock on the door to say that it's sorted and didn't need access to your home.
Here's one example.
If you are not getting the three green lights on the front of the Router or there is no BT line / socket to plug the Router into, then phone the NOW Broadband Team.