Put "unprofessional" (3)
This clue is a double definition.
'put' is the first definition.
('lay' can be a synonym of 'put')
'unprofessional' is the second definition.
(I've seen this before)
(Other definitions for lay that I've seen before include "Not professional", "in which hens regularly produce eggs?", "Song-ballad", "Air", "Of bird, produce egg".)