(1) Without prejudice to the provisions of sections 40 and 41, no person, who is not a registered dealer, shall collect from any person any amount, by whatever name or description it may be called, towards or purporting to be tax on sale of goods.
     (2) No registered dealer shall collect from any person any such amount exceeding the amount arrived at after applying the rate of tax specified under section 14 to the sale price of the goods sold.
     (3) If any person or a registered dealer contravenes the provisions of sub-section (1) or sub-section (2), the prescribed authority shall, after giving an opportunity of being heard in the manner prescribed, by an order in writing direct that such person or registered dealer shall pay by way of penalty a sum equal to twice the amount collected in contravention of the provisions of sub-sections (1) and (2).