Unhappy about shops creating promotional opportunity (5,2)
I believe the answer is:
small ad
'promotional opportunity' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'unhappy about shops' is the wordplay.
'unhappy' becomes 'sad' (associated in meaning).
'about' is an insertion indicator.
'shops' becomes 'mall'.
'sad' placed around 'mall' is 'SMALL AD'.
'creating' is the link.
Can you help me to learn more?
(Other definitions for small ad that I've seen before include "Classified advertisement" , "Classified advert" .)