Wrong, incorrect (5)
I believe the answer is:
amiss
I believe this clue is a double definition.
'wrong' is the first definition.
(I know that wrong can be written as amiss)
'incorrect' is the second definition.
(thesaurus)
(Other definitions for amiss that I've seen before include "Wrong; inaccurate" , "Wrong - awry" , "Faulty" , "inappropriately" , "Mistaken" .)