Hathway spam issue

After a lot of spam calls for months, now they are sending me legal threats. From the first day, i am asking them to take away router. They keep calling me daily and finally sent me a link for filing address for router pickup, I filled address and asked them to take. They called me and asked around 400 for keeping router with me all these days. I said I am not going to give a penny and asked to take away router.