It's not me, it's you! (6,6)
I believe the answer is:
second person
'you' is the definition.
(I've seen this before)
'it's not me it's' is the wordplay.
I cannot really understand how this works, but
'not' could be 'con' (I've seen this in other clues) and 'con' is found in the answer.
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Another definition for second person that I've seen is " Category governing the addressee (gram.)".)