Punjab National Bank [PNB] — Payment not received

Address:

Tinsukia

I have order an item from amazon on 19 oct 2020 and also canceled the product on same day and they initiated the refund successfully. But till now I haven’t received the amount.Amazon has also given in written form with reference number and transaction id that they had successfully refunded.
While sharing this issue with bank customer care there they are not helping me while they saying we cannot take any complaint regarding this . Please help me to get the amount back