¹[193B.] The Board may, on its own motion ²[* * *] within one year of the passing of an order, rectify any mistake or error which is apparent from the record in any order passed by it under any provision of this Act or the rules made thereunder: Provided that no such rectification which has the effect of enhancing any penalty or fine or requiring the payment of a greater amount of duty shall be made unless the person affected by such rectification has been given an opportunity of being heard in person or through a counsel or other person duly authorised by him.]