Section 45, The Goods and Services Tax Act, 2009

(1) The original or a certified copy of a notice ofassessment is receivable in proceedings as conclusive evidence that the assessment has been duly made and, except in proceedings in relation to the assessment under Part XVII, that the amount and all particulars of the assessment are correct. (2) No assessment made, issued or executed under this Act may be– (a) quashed or deemed to be void or voidable for want of form; or (b) affected by reason of mistake, defect or omission in it, if it is, in substance and effect, in conformity with this Act and the person assessed or intended to be assessed is designated in it according to common understanding. PART XII–POWERS AND DUTIES OF THE COMMISSIONER-GENERAL