MTNL
Internet not working properly

I have a mtnl connection . the mtnl broadband service so poor that the modem gets restarted in every ten minutes and sometimes connections is not available between 3 to 5 pm

the connection sometimes gets so slow .we have taken the sceam of 512 kbps but the internet works like 128 kbps . i a have to do some work on internet i cant use net steadily for 15 minutes also the internet connection gets lost in between and i have to wait for net connection getting back then i resume my work

i experience this problem whenever i use internet

i am fed up from this third class connection please look at my problem as soon as possible