HDFC Bank — not received cash back

Respected sir/madam,
I have purchased apple macbook on 30th april 2020 for rs 70000 through my hdfc debit card, in that i was entitled for a cashback of 6000 within 120 days from the last date of purchased month. Till now i haven't received any cashback points in my account. So please go through and need the helpful.
Herewith i am attaching details and a bill copy.

Transaction id : [protected]
Date of transaction : 30th april 2020