Air India — excess money taken without giving a receipt

Address:	Gorakhpur, Uttar Pradesh
Website:	Www.airindia.com

I have booked a seat in air india flight from gorakhpur to delhi vide e-ticket number:[protected] for journey date 07 may 18 and paid rs 7910 through credit card.
Thereafter, i could not perform this journey on 07 may 18 and i had to change date of journey to 08 may 18. I was told to pay date change penalty of rs 2625. This money i was told to pay in cash at gorakhpur air india ticket counter and i was told that the receipt for this payment will be sent to you on your registered email address. However, the same is still awaited. The revised ticket shows original credit card payment amount and it does not reflect additional cash payment made by me. Please look into the matter and send updated ticket/receipt with details of cash payment.