Against a summon sent to me by an IT company to me

I joined and left an Indian IT company in Hyderbad within 2 days. I joined the company during May 2012 and left during same month and within 2 days by informing them through my personal Email and explaining my urgency and personal reasons via Phone and email. Dear Expert, During joining there I signed all the contaract of employement letter as per thier norms as per their standard. They are CMM5 level company. Now, I recived first a letter 'Legal Notice' from lawyer of the company by asking the money for settlement and I responded to them by sending the asked amount via DD by courier. Called via phone and got acknowlegement via phone from them. Further, I did not keep any track as well no proof of payment I can found as send it through DD and missed the copy of it. Now all of a sudden we recieved a letter of Summon from court and to appear on next 30th Dec which next 7 days to the court in Hyderabad. I am totally clueless and scared as I have no idea on this matter at all. I am looking for a help from expert out here. Best Regards