Air India Express — Refund are not returning of cancelled flight

I booked a ticket online at air India website on 25 th Oct 2020 from agartala to Jammu. Ticket was issued and passenger name was Rajendra Kumar Mistri.
On dated 02 nov 2020, I got a mail on from Air India one flight kolkatta to delhi is cancelled and it will be depart next day so I called to customer care for cancel all connecting flight and they replied you have send a mail at [protected]@airindia.in.
On same day I mailed to [protected]@airindia.in for cancelled all connecting flight. I once again mailed to 3rd and 11th Nov 2020 but no any kind of response given by airline and no refund has been issued /given me.
On dated 22 Dec 2020, I also mailed to [protected]@airindiaexpress.in for refund but result is same, no response given of this mail.
So kindly do needful action and please help to rufund the whole amount (Rs. 9577) in this regard.
I shall be highly grateful of you.
Thanking you.
All related documents are attached in this mail.
My contact numbers are [protected]., [protected]