Putting a limit on an invoice makes it void (7)
I believe the answer is:
invalid
'void' is the definition.
(similar in meaning)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for invalid that I've seen before include "Disable" , "Void - sickly person" , "to be in poor health" , "Permanently sick person" , "Null and void" .)