Rectification of mistakes.

At any time within one year from the date of any order passed by it, the Corporation may, on its own motion, rectify any mistake apparent from the record, and shall, within a like period, rectify any such mistake which has been brought to the notice of the Corporation by any person affected by any order issued under this Act: Provided that no such rectification shall be made which has the effect of enhancing the liability of any person unless that person has been given a reasonable opportunity of being heard in the matter.