Vision Bpo Services — pressuring to pay charges

Address:

Office No.9, 3rd floor, above IndusInd Bank, Near Mico Circle, Nashik–422005, Maharashtra, (I)., Nashik, Maharashtra, 422005

I have started online work. But due to the confusion of their i have denied to do work on mail and on whatsupp. But they told me to pay r. S. 1200 as per agreement ot we will file a case against me. Now they are pressurising me legally yo pay rs. 3400. Now what can i do?
They sent me a message below:-

As you have denied to close the case by paying the portal and maintenance charges according to the contract which was signed by you. We have to proceed legally and your case will be filed in nashik district court. You will be charged under sec 73, 74 and 75 as per the indian contract act.
Regards,

Legal department.
Vision bpo services
[protected]

Please help