Notice love causes bother (3)
I believe the answer is:
ado
'bother' is the definition.
(both can mean fuss or commotion)
'notice love' is the wordplay.
'notice' becomes 'ad' (both can mean an advertisement).
'love' becomes 'o' (love means zero in tennis).
'ad'+'o'='ADO'
'causes' is the link.
(Other definitions for ado that I've seen before include "agitation" , "hoo-hah" , "stir" , "Song and dance" , "Fuss or bustle" .)