A charge sheet? (5,4)
I believe the answer is:
price list
'sheet?' is the definition.
The definition and answer can be both related to communication as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
'a charge' is the wordplay.
I cannot quite understand how this works, but
'charge' could be 'price' (I've seen this in another clue) and 'price' is located in the answer.
The remaining letters 'list' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for price list that I've seen before include "Tariff" , "what things cost" .)