net plus broadband - Security Amount not Refunding company

I had applied for broadband connection on * march **** and paid *** rupees as a security refundable, but my broadband connection not setup yet even not received security amount yet.so I want to refund my documents and security amount ***.
I had called many times sales person and company customer care also sent emails for refund security amount but no one responding me even not attending my call.
I am attaching receipt snaps for reference.
I have also customer care email conversation screen shots ,but website allowing only one file can upload.