Air India — Full refund of air ticket

Air india give me only one ticket refund instead of two ticket
many time I have mailed to air india they told that refund is given and give a same answer for two ticket refund incited on 08 sep but I got only one ticket refund
So please give my full refund of all two tickets
Ticket details are
Please provide my full refund of e ticket no.[protected] &[protected]
Travel date - 25 Apr 21

Date of book - 05 Apr 21

Date of cancellation - 05 Apr 21

Delhi - Chennai

Flight no. - AI-429