Intentionally signed off after purchase delivered (2,6)
I believe the answer is:
by design
'intentionally' is the definition.
(synonyms)
'signed off after purchase delivered' is the wordplay.
I cannot quite see how this works, but
an anagram of 'signed' is 'design' which is present in the answer.
The remaining letters 'by' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for by design that I've seen before include "Intentionally" , "On purpose" .)