Amazon India — I have not received my refund till now

Address:

Durg, Chhattisgarh, 490001

On august 23, i ordered 434 rupees worth of submersible pump (With delivery charges). Order id:[protected] and on september 7, another brand pump was delivered to me which i returned on september 8. And since then, it has been 3 months since i have not received my money back. When i contacted twitter several times, i was told on october 7 that by the 15th of october the refund will be in my account. Which has not been deposited in my account till now. On the second contact, for the third time, it has been said that the money has been sent from amazon and for some reason i have not been deposited in my bank account, then i was asked to contact the bank. But in the bank it was found that no deposit of 434 rupees has been made in my account. But now no response is given on contacting in amazon