Company not refunding money and also demanded money

I made an account on Quikr to find part time jobs as I am a student. After some days I received a message on my mobile saying that they provide home based typing work and you can earn Rs. 18000-30000/- per month. So I called the number and they asked me to visit their office in Kirti Nagr, New Delhi for an interview and training session. I went there on 23rd March 2019 Saturday. They told me that it is a simple Data Entry work and I will be provided with an online contract and link, and after accepting it I can start my work and within two days of completion, I will receive the amount. Then the lady there asked me to fill a form and pay her Rs. 3500/- to take the project. I questioned them and they said that it is refundable and I will get it back in my account. She said that without paying the money I won’t get the work. So I paid the amount and my details. On 25th March 2019 I received the links to start my work and the deadline as well which was 14th April 2019.
I successfully submitted the work on 14th April and waited for their response, but they kept on delaying it.
After repeatedly calling and emailing them for the next 11 days I got a response from them stating that the QC report is not accurate and I am not liable to payment. I went through the report and double cross checked it and to my finding there were no errors as stated by them! Also the report sent by them was false and fabricated. And, the mathematical calculation was wrong about the errors. I also sent them multiple emails about the same as well as the errors in their own false report. I told them that please make my payment as I am liable to it. They are harassing me continuously in all forms and are even not responding.
Firstly, the work sent by them was extremely tedious and I used to spend 15 plus hours every day to make sure that I meet the deadline. On 24th April they said that they will pay me my amount i.e Rs. 31,500, but now they have refused and have also denied to pay my security money which was refundable and now they are harassing and ill treating me.
Respected team, I am a student and I am saving for my education as it is expensive. It was my hard work, labour and precious time which was invested to give them complete and correct work. I have invested my precious 300 working hours to meet their unrealistic deadline. And now they are just harassing me.
Please help me to get my amount back i.e Rs. 31500. I request you to please help me.

Akansha Dhar
Malviya Nagar, NEW DELHI 110017
Email: dxxxxxxxxxxx8@gmail.com