Punjab National Bank [PNB] — Refund initiated by amazon but still payment not received.

I was ordered wecool moonwalk bluetooth headset on amazon on 26/03/2021 order id[protected] .Total price of that product Rs-799 and i paid Rs-50 rupees from amazon pay balance and remain balance i paid from my PNB DEBIT card which is Rs-748 . on this date i research about the product and i was thought that is not value for money, so i cancelled it. The amazon pay i rs-50 greceived this date but PNB debit bank balance not received, from amazon they send me a mail that your refund will be receive in 3-5 days.but refund not credited to my bank account.after 5 days i try to call amazon and i told why refund not reflect my bank account, then they told me refund intiated already from amazon and they give me a reference no-74332741086108505332628. so i called my bank customer care but they told me any refund not initiated to my bank account.and i also cheked my bank balance yet my refund balance is not reflected my account. please help me.