Unable to make minimum amount due on credit card might receive notice

I have an SBI i credit card from last 3 or 4 months i was unable to make minimum amount due on the card what every was possible i have made payment my payment day is first of every month i had talk to customer care and written email to SBI to change my payment date as i get paid between 7th and 12th of every month when my salary gets credited i use to make payment i never asked SBI to remove and late payment or any other charges i received message today that legal notice has been sent to me. I have all the intention to make payment but right now i am not in position to make the complete payment is there any way that i can make small payments of 5 to 7 thousand every month and down the line after 5 or 6 months i start making more payment and get it closed . What would be the step forward?