I Solutions — captcha fraud and blackmail

Address: 35/F ABRAcade, Ausha Nagar, Latur, Maharashtra, 413531

Around the beginning of feb, i was contacted by this person called "payal sindhi" who came up with this proposition to be able to earn ₹22, 500 in 10 days by solving 10, 000 captcha with an accuracy of 90%. She also laid the condition that if could not complete the task, i would have to pay them ₹5000 from my earnings. I was in dire need of money at that time, owing to an upcoming exam, so i thought this was a sign from above and signed up for it.
A couple days into it, i came across an article that said that captcha solving is a crime. Moreover, the app that they had asked me to download, the one on which i was supposed to work, was also faulty! Panicking, i called their helpline but it was always out of coverage area. I decided to called 'payal sindhi'.in the beginning she wouldn't even pick my calls up, but after another 5-7 times of continuing to dial she finally picked up - and was immensely rude. She said that i couldn't terminate the contract now and that i'd have to pay them ₹5000 if i did. Saying this she cut the call in my face!
I decided to drop the activity anyway because i did not want to fall into a deeper pit than i already was in.
After 12-13 days, i received a push notification saying that if i didn't want be booked for breach of contract, i should contact the given number. The number, when i checked on truecaller said "fraud bewra of captcha" - i don't know what that is supposed to mean. I called that person and he introduced himself as adv. Kunal shah. He said that i'd have to pay his client an amount of almost 13k now. I blocked the number, but the messages still continue and they keep blackmailing me saying that if i don't pay them, they would take me to court.
I do not know what to do... Please help..