Tata SBI Credit Card — Not update the data

Address:	New Delhi, Delhi, 110083
Website:	TATA SBI credit card

I have made a transaction via amazon of on 6 July 2016 around 13500 something and while I was purchasing I have selected the 9 months installment but as per the statement it is showing the whole amount and interest has been created as per the whole amount so I called to customer care and lodge a complaint and the customer care executive told me that I will get a call before 29 July 2016 however I still haven't received any call from your side and tomorrow means 31 July is the due date so who is going to tell me that how much amount I have to pay even i called again customer care two time but firstly they disconnected the call after 14 minutes and then waiting queue is 28 minutes so i don't think so this is acceptable. This is happening third time now i think stop the services.