Under which circumstances a director shall vacate his office?

The composition of the Board of Directors of a listed company as on 31-03-2023 comprised of: (i) Mr. A, Director, (ii) Mr. B, Director (iii) Mr. C, Director (iv) Mr. D, Director, (v) Mrs. E, Independent Director, (vi) Mr. F, Independent Director and (vii) Mr. G, Independent Director. Mr. D & Mrs. E vacated their office of Director on 15-04-2023. You are required to examine with reference for the provisions of the Companies Act, 2013 and what course of action would you suggest which can be taken up by the Company in this regard?