Hathway — Hathway calls harassment

Hi,
I have disconnected my hathway broadband and the agent has collected back the router as well.
Its been more than 2 months but still each and every day i am getting 4 to 5 calls to renew the account and 4 to 5 messages for the renewal.
I have been telling the same reason to each and every person from hathway customer team that i have disconnected and router has been returned. They say they will update in the system, but no action has been taken.
1. I have registered complaints via hathway home page but no action taken.
2. Have called to pathetic customer number and gave complaint, they say they will update but no action has been taken.
3. Have mailed to hathway helpdesk, but no action has been taken.
4. Security deposit of rs.400 also not refunded back.