Pardon me sir! Is no problem! (9)
I believe the answer is:
remission
'pardon' is the definition.
(remission is a kind of pardon)
'me sir is no problem' is the wordplay.
'problem' indicates anagramming the letters.
'me'+'sir'+'is'+'no'='mesirisno'
'mesirisno' with letters rearranged gives 'REMISSION'.
(Other definitions for remission that I've seen before include "Reduction of sentence" , "Relief" , "Cancellation (of a debt)" , "Reduction of charge" , "Reprieve" .)