21. Powers of [Authority] regarding returns. -- (1) If it appears to the [Authority] that any return furnished to him under the provisions of this Act is inaccurate or defective in any respect, he may--
(a) require from the insurer such further information, certified if he so directs by an auditor or actuary, as he may consider necessary to correct or supplement such return;
(b) call upon the insurer to submit for his examination at the principal place of business of the insurer in [India] any book of account, register or other document or to supply any statement which his may specify in a notice served on the insurer for the purpose;
(c) examine any office of the insurer on oath in relation to the return;
(d) decline to accept any such return unless the inaccuracy has been corrected or the deficiency has been supplied before the expiry of one month from the date on which the requisition asking for correction of (he inaccuracy or supply of the deficiency was delivered to the insurer [or of such further time as the [Authority] may specify in the requisition] and if him declines to accept any such return, the insurer shall be deemed to have failed to comply with the provisions of section 15 *** [or section 28] [or section 28A or section 28B or section 64V] relating to the furnishing of returns.
[(2) The Securities Appellate Tribunal may, on the application of an insurer and after hearing the Authority, cancel any order made by the Authority under clause (d) of sub-section (1) or may direct the acceptance of such a return which the Authority has declined to accept, if the insurer satisfies the Tribunal that the action of the Authority was in the circumstances unreasonable:
Provided that no application under this sub-section shall be entertained unless it is made before the expiration of four months from the date when the Authority made the order or declined to accept the return.]