For the benefit of people that would like to help you, but don't have the puzzle, it's best to post the full clues, numbers of letters & any you've already placed - thanks! :-))
I was only looking for answers from those who have done the puzzle, but ok:
21a Letters received ahead of good job taken with airline, p???b??, I'm thinking plumbob but not sure.
17d Snark and it's strange language, ?a???r?t
22d Misleading explanation for grand deficit, ??o?s
Thanks in advance