Not much we can do on here as we are just customers like you.
You will need to keep pestering the broadband team until it’s resolved. All I can suggest is to use your mobile as a hot spot until your broadband is up and running again.
Using Now Broadband for business is like buying a car when you need a van 😛
But you should find the compensation you will automatically get for being without service will more than fund a WiFi hotspot on your phone, if you have a decent enough data plan.