Akt Enterprises — the company is blackmailing

I'm janhavi. I was searching for an online home based job but i was not able to find a suitable job. One day suddenly i received a call from akt company, they offered me a job with a target of completing 7000 captchas in 7 days which was nearly impossible to do as the captchas were not clear. It was impossible to recognise difference between capital i and small l, due to which i was not able to complete the target. They asked for my signature and my adhar card which i provided them.. But now they are blackmailing me that they will file a case against me. They asked to contact but they are not answering any of the call.