State Bank Of India [SBI] — refund initiated from amazon but not credited in my bank account

Address:

Saharsa, Bihar

I have purchased an item on 14th october 2019 from amazon by online transaction using my sbi bank account. But for any reason my item has been cancelled and the refund was initiated from amazon on 19th october 2019 and the refund reference is #[protected].
But i didn't receive my refundable money in my bank account yet.
Please help me.