Paytm Mobile Solutions — paytm refuses 6000 cashback as promised - for s9+ phone

Website:

www.paytm.com

My order number: [protected].
I made a purchase of samsung s9 + during the initial days of its release at a samsung phone showroom.
During purchase, i was told i would get 6000 cash back and the message was shown on the paytm mall app that i am eligible for cashback.
However after purchase, they told me to wait for 10 days for the cash back to be credited. After 10 days they say all crap reasons like your card is not eligible for this offer, your card cannot receive cash back blah blah.
Now is this a new trick of paytm? Promising cashback, making them wait for 10 days and then say no cash back - they copy paste a standard message they have for any issues/complaints you raise against the cashback.

These are cheap tricks! I would rather purchase a phone in other shops where cash back would be credited to my creditcard rather than being fooled by paytm.

Now provide me with cashback or take back your phone!
You dont deserve any trust paytm...!