Your wireless router may not be a modem as well. When I tried to upgrade with BT, they sent me a wireless router and a modem - very confusing. Decided not to go with that option and I am now with Sky and they sent me a modem which is also a wireless router, i.e. just one box - nice and simple
It does sound like Sefton is right and that you need to add the modem back into the mix, at the right point of course.
