Advice for payment recovery from corporate company in delhi

Dear Sir, My name is Narender Kumar and i am doing freelance HR/ Consultancy work from home as i am unemployed since last 6 months so i started my freelance HR/ Consultancy work. I provide manpower to the corporate across business functions. I have signed up a agreement with one company based out Delhi for providing manpower and filling up their very senior positions. following was the Terms and conditions on manpower * Recruitment Fees: 6% on total annual CTC of the candidates * Payment time: Withing 30 days after joining the Candidates * Replacement: 90 days if any candidate left the company withing 90 days then we shall provide free replacement in that company Now I had placed candidates as CFO in that company his joining date was on 15.03.2019 and i had raised the invoice on 15.04.2019. I have still not being paid by the company which was due on 15.04.2019. I have spoken with their top management several times but they are not paying me. So, can you help in this regards?