In message
, CJB
writes

ZSL stated that they needed TWO *paper* tickets from 'outside' London
to London - although they couldn't define the term 'outside' nor the
exact destination London station required.

The terms and conditions state that all you need are two paper tickets
with the National Rail symbol printed on them, valid for the date of
admission to the attraction, which it appears you had.

There is no requirement to travel to any particular station in London
or, indeed, for you to travel to London at all. You merely have to have
used National Rail with a paper ticket on that date.

Write to London Zoo and ask for a refund. If they decline, complain to
customer services at FGW.
--
Paul Terry