I've paid £23.97 for 6 months entertainment but when I got to passes it just says start free trial and if I try to start a program it just takes me to the section to start trial. My order reference is 451M136031213.
See if live chat can figure out what's happening where you can't see the 6 month entertainment pass on your account.
Also i am assuming you haven't got multiple nowtv accounts and checking for this 6 month pass in the wrong account.
Here's a link to live chat.