HDB Financial Services — Cash back issue making fraudulent activity

Address:

132, 2nd Floor, Sweety Mall, Kodambakkam High Road, Tirumurthy Nagar, Nungambakkam, Chennai, Tamil Nadu 600034

Dear sir

I have purchased ac in ratna fan t nagar via hdb financial service through emi option while purchasing i got offer of 4000 cash back in hdb and they have taken signature for 4000 rupees cashback from me. Now i have paid all my outstanding emi when i asked cashback for cash back they sent jus 2000 rupees and that's it if i ask they are contact branch bla bla. I have dropped serveral mails to them they are not responding