law: 22. Collection of tax only by registered dealers.
  (1) No person who is not a registered dealer shall collect in respect of any sale of goods by him in Delhi any amount by way of tax under this Act, and no registered dealer shall make any such collection except in accordance with this Act and the rules made thereunder.
  (2) Notwithstanding anything contained in sub-section (1), a dealer who has been permitted by the Commissioner to make a lump sum payment under section 29 shall not collect any sum by way of tax on the sale of goods if made during the period of which such lump sum payment relates.