Fail to get a girl's address (4)
I believe the answer is:
miss
This clue is a double definition.
'fail to get' is the first definition.
(I've seen this in another clue)
'a girl's address' is the second definition.
(term of address for a girl)
(Other definitions for miss that I've seen before include "Fail to perceive" , "Overlook - misfire - young lady" , "Feel the loss of - schoolgirl" , "Pine for - young lady" , "Feel the absence of" .)