Zet Technology — Fraud online work job

I was searching on hob on Qikr and applied on that.
I got a call from a person saying they have captcha filling work for me . I had to do 10000 captcha out of which 9000 should be correct . I agreed and they sent me a mail with a link to open, there i was asked an OTP which the company person gave me as it did not come on my phone . They sent me login id and password and said to start work at 6pm . When i tried logging in at 6 it said work not started yet . I tried till 9 but couldnt open it . Next day i it opened and i filled 1000 captcha but on next day when the captcha correct are shown it was writtem that i had only filled 400 captcha .
This seemed a bit wrong and i checked online about this compnay where it showed about the fraud the were doing.
I messaged to the person who had called me from the company saying That they are fraud as their contact number eas also showing fraud in true caller when i checked but they did not respond So i thought that matter is resolved but a few days back i got a mail saying i have not done work i a case will be registered if i dont pay . They are threatening me and causing mental Harrasment to me .
Kindly help me resolve this issue .