IRCTC - Denied to refund the cancellation charges which I have to pay for their mistake

They are doing a scam.Yesterday i was booking a ticket so when i proceeded to the payment page and paid with my debit card it showed payment failure and it redirected me to the payment page again so i again paid the amount with my Debit card and then two tickets were booked and twice amount was deducted.So when i called their customer care and asked for refund of cancellation charges which i have to pay to cancel one of the tickets they first talked to me rudely and denied to pay cancellation charges and when I asked them to transfer this call to their senior department they denied to do that and hang up the call.I again called their customer care but they didn't transfer the call to their senior department and again hang up the call.This is simply a fraud why I will pay the cancellation charges when it is not my mistake the app again redirected me to the payment page so I again paid the amount thinking that it was payment failure.The page didn't showed that your payment is in pending status and also no messages were sent to my mobile number that your amount has been deducted.