HDFC Bank — Amazon amount refunded but not reflecting in my account

Amazon has sent a mail saying the amount has been refunded back into the hdfc account through net banking but the amount is not reflecting in my account. It's been 5 days since the message came.

My bank account number is [protected]

Amazon company has sent me a reference number for the refund. When will i get the refund back into the account? The amount is huge.