"Bug" Living World Purchased; not ENABLED?
You might need to relog. When I bought HoT it needed me to relog before I could play the content. If this doesn’t work you should open a support ticket.
As indicated on the in-game Bug Report window, no response(s) will be provided.
To assure a response, one can submit a request via the ‘Support’ link above/below.
Good luck.