@Anonymous User
Welcome to the forum.
If it's the type of network where once you've connected to wifi you need to open up a web browser and authenticate on that before you get access, then unfortunately that type of connection isn't compatible with the NOW TV box - it will look as if it is connected but it isn't actually authenticated to access anything.
If that's the case then the best thing to do is contact the technical support team for the broadband service, they may be able to authorise the box directly using its MAC address, which can be found on the sticker on the bottom of the box.
If they aren't able to do that then you'd need to watch on a different device such as laptop, tablet, mobile.
Alternately you'd need to look at buying either a Roku streaming stick or Roku box as these have the ability to connect to such networks, or a device something like the HooToo TripMate Router (from eg Amazon) that will connect to the wifi and then create its own wifi network your box can connect to. However I can't guarantee how well these would work with your particular network - reading on the web both get mixed reviews with regards reliably connecting to those types of wifi networks.
Personally, if tech support can't help I'd stick to using a different device.
