Refund not received

I ordered a mobile phone on Amazon paid for it through debit card but later cancelled due to delay in delivery. I ask them to refund the amount 1299 into my account they say they’ve refunded the amount and provided the refund reference number 75260828175020908661646. And told to call bank of India for same . But till date I havent got my refund into my account. I tried calling Bank of India which never works. At last resort I tried writing the same to you. I hope to seek the redressal for the same.
Thank You , Sunil Pandey