PNB — Refund issued by Amazon but not received in my pnb account as yet

I purchased an item from Amazon for Rs/- 9800 on 24 th January but due to quality issue I returned the same to Amazon .Amazon issued refund of R s/-9800 on 31 January 2021, but I did not get the refund in my PNB account. After complaining, Amazon provided me the REFUND REFERENCE NO- 30005110241024174457505.According to Amazon details refund has been successfully done. When almost ten days passed, I did not get the refund, then with this reference number I approached PNB customer care. Customer care executives refused to help me and told that we cannot track this reference 30005110241024174457505, because it is not being displayed on our system. Then I asked for charge dispute form, the executive told that such form is not available or in practice in PNB. Several times I called Amazon customer care and PNB customer care but I did not get my refund so far. Both of them are making liable to each other but not helping me. Where has my refund gone or stuck? Please help me.