Nextra Teleservices — Router burned

Nextra provides cheap quality router, because of over heat adapter got blast and sound was so loud even neighbors came out from their home and when i filed a complaint they sent a second hand router and charged 500rs for it, and after using it 1 hour that router stopped working, i am just fedup with their services, it's been like 5 month since i am using their service and not a single week gone without an error or network failure. My id 2142578