I-Way Solution — unauthorised charges and harassment

I was working for them where they provided me with 12000 captcha and told me that 10800 captchas should be correct to get ₹24000 and they will deducted the registration fee of 6000 from it. But somehow i couldn't complete my work so they called me up and told me to pay ₹10, 510 or else my case would be taken to the court. As they said i paid them. But later on they called me up and told me to pay ₹31000 to cancel my name from the company. They sending me continous mail and telling me that if i don't pay then my case will be taken to the court. When i told them that the agreement had nothing mentioned to pay so much money then they started to scare me upwhat should i do now