MTNL Broadband service
No xdsl light.and disapear in every 2 min

I am complaining from the last 30 days and there is no xdsl light .. it comes only for 5 min ..if i complaint about xdsl light every time custmer care giving me complaint no.. 40500023.. and no body is coming to solve the problem .. my modem no is UT-304R2 .. plz solve my problem as soon as possible ..