State Bank Of India [SBI] — unable to solve genuine problem

Address: New Delhi, Delhi, 110078

I was sbi credit card holder from feb, 2004 to june 2015 and had been making timely payments for all the above mentioned periods
I blocked this card in june 2014 due to some reason, but had not received any new card in lieu of the blocked card. Since then, i am unable to use the services of the sbi credit card.
I tried to contact customer care helpline many times but no one was available to help it out.
I even mailed at [protected]@sbicreditcard.com and [protected]@sbicard.com regarding the same many a times but even they were unable to solve the problem.
To my utter surprise, bills were generated for statement dated 6 dec 2014 onwards whereas i was unable to use the services to the said credit card
Lastly, i gave my consent to terminate the services in aug 2015
Services provided by sbi credit card were really bad; it affected my cibil score also, even when there was no fault on my side.