Sorry to hear you're still having trouble with this.
I've just checked this on the app and Ghostbusters is definitely available to stream. First, open up the app and type Ghostbusters into the search bar. Select Ghostbusters (2016) and you should get a full synopsis of the film as well as the options for 'Watch' and 'Trailer'. Select 'Watch' to view the film.
Let me know how it goes!
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