Non payment of Salary by the company

I was terminated by my company in August where I not even work of over 45 days.Now my F&F is pending and when I contacted the HR she sent me a no dues form which states " Receiving Letter I, Deepika Pandita, D/o have received from ‘xxx PVT LTD sum of Rs. xxxxx/-By way of online transfer as my salary of August month from 1st to 21st, including cab reimbursement of 1200, with all my claims against the management. I further declare that on payment of said sum I have no further claim whatsoever. I also declare that I have received the above said amount as online transfer as August month’s salary ‘xxxxx PVT LTD’. Upon receiving the above said amount I hereby declare the company has no financial liability with regard to all my salary and dues. I will not raise any claim or demand, whatsoever against the company. ACCEPTED BY: Name: Place: Date: Mobile No: PAN: Home Address: Signature: And I have not received the dues and they are telling me to sign in advance. Please let me know