Indian Bank — refund never processed

Address: 560070

On 8-4-19 I tried to book an product from Amazon app but it was not placed, because the payment was failure. But money ₹439 is deducted from my account as POS transaction. I tried to pay using debit card. It has been more than 40 days, still I didn't get back my amount. I also raised a complaint online in Indian Bank website which is closed now without resolving the problem.