Belgian port doesn't change (6)
I believe the answer is:
ostend
'belgian port' is the definition.
(I've seen this in another clue)
'doesn't change' is the wordplay.
'change' is an anagram indicator.
'doesnt' is an anagram of 'OSTEND'.
(Other definitions for ostend that I've seen before include "Belgian ferry port" , "Channel port" , "Port in Belgium" , "cross-channel port" , "European port" .)