Nextra Broadband — poor service, internet is always slow and sometime down

I have registered a complaint on faulty router change 6 days back, but still no technical person have made a visited to change it. Customer care is worst in the country when i ask them to give their manager number and name the representative told me they can't give their manager name and neither they are allowed to transfer call to the team lead or manager. I am really surprised how the hell these people are running this company.