Employment bond

Dear Lawyers, Greetings.. I resigned from a Indian Company and as per their appointment letter they mentioned clause of Employment Fidelity Bond - "after international Exposure Employee should not resign at least for the period of one year else he has to pay 4 months salary, however i left the company before before one year, after my resignation i received a letter from my HR stating that i need to submit 10 months salary ( 4 months salary as per Employment Fidelity Bond & 6 month salary as leaving organization before 2 years), i did not respond to the letter however few days letter i received a legal notice by a There lawer stating to deposit 10 month salary (same as mentioned in letter by HR), I replied through my legal advisor there was no bons signed between me and company, however as per appointment letter there was Employment Fidelity Bond - and i am ready to pay that amount and asked to give us exact amount that needed to be paid. However in return they filed as case against me at faridabad district session court. Please note in appointment letter there was no such clause- that employee can not leav organization before 2 years elso he has to pay 6 months salary. Also please consider since i was working in Export department there were many stamp paper was signed during my tenure by me as were needed by shipment clearance agents and regulatory bodies as affidavits few of they were blank as well.. please advise what should i do..?? what would be the percentage of winning the case, i am ready to give 4 month salary as per their appointment letter.? What will be the maximum i need to pay to my company if i lose.? I am totally confused please advice, what should be my action plan ?