IT Return on the interest earned in joint saving account

GNSah (Engineer) (22 Points)

31 March 2021  
Dear Sir,
I filed income tax ITR 01 for Ay 2020-21. My Income tax got successfully processed in Jan 2021. Yesterday I got a notification from income tax regarding e-Campaign High Value Transactions for Rs 50000. In this notification they have mentioned transactions related to "Interest paid by bank for saving account". I did not declared this amount during ITR filling as this amount was not mentioned in Form 26-AS.
 
When I checked my saving account transactions details then I found that the interest has been mentioned from my joint saving account with my wife. I am the primary account holder and my wife is secondary account holder. Generally I deposit money in this account as she is not earning. 
 
Can the saving interest earned in this account be shared by both my wife (50%) and me (50%) ? If yes, then does she need to fill IT return by showing 50% of the total amount deposited by me as a gift in this account?

Kindly suggest how to share the interest earned in this joint account by me and my wife.

Also how to address this notifications.

Regards