Techno Enterprise Capthca Work — unauthorized charges

Dear madam/sir
I received a work from Techno Enterprise. It is a cpatcha filling work about 10, 000 captcha have to filled in 10days with 90% accuracy.They ask my signature in a bond to proceed the work in that if am fail to work I have to pay 5000 rupees as penalty charge. I am failed to complete the work so I paid 5000 rupees to him. I received a NOC for that payment.Next day I received call from company by another person he asked me to do you want to receive work from my company or not? I said I don't want to work with your company then he said I have to pay 16890 rupees as cancellation fee but it was not in the agreement to pay for the company.But he doesn't hear my words I am not paid the amount in 2 hours then he said he will take that action against me and send a notice to me. I am frightened about case.I was pay 8500 as cancellation fee.after that I received NOC from company I mail but still they called me to pay the money. I received calls from different numbers and asked me pay the amount within 2 hours or 1 hour. They warn me if I am not paid money to them they will take legal action against me. They increase the amount that has to pay immediately .Please take serious action on them .