Citibank — hdfc netbanking transaction success, amount is not credited to my citibank credit card

I have made a hdfc neft transaction on 27 set 2018 of amount 4709 to citibank credit card but citibank is saying that they have not received the amount as per their neft report and hdfc bank is saying that they have credited the amount.

So where is that amount went? I have shared all the proofs with citibank through their mail.

I feel helpless as these guys are not helping at all and i am feeling like i have lost my money.

I need your support. Please help.