Amazon India — samsung galaxy m30s

Sir i am sanchit kumar mishra and i had ordered samsung galaxy m30s on 29.9.2019 and paid it's amount by my debit card and next day i had cancelled it on 30.9.2019 and i was aware that the amount will reflect in your account in 3-4working days. So i had waited till 5 october and on this day i made a call to customer care and they said me that please wait till 7 october we had refunded your money on 30.9.2019 and it will take time till 7 october to reflect in your bank account. Then also i had waited and again on 8 october i had made a call to customer care and they said that sport sir for this your money will be reflected before 10 of october. And i had waited till 10 octoberagain my money was not reflecting in my account. Then to i had call customer care today (11.10.2019) and they said that sir i am sending a reference no. Related to your refund and if you will go to the bank then they will reflect your amount in your bank account. So today (11.10.2019) i had the to the bank with that reference no. And then bank had tell me the this reference no. Is invalid and they had not even did any type of refund to this account. After that when i am trying to again call to customer care they are not responding my call i had called them atleast 10 to 20 times but there is not a responds of a single call. I am sending the email sent by them. So sir please take and strict action towards them to refund my money.
Thanking you