BSNL modem — internet disconnected

my pcs internet is automatically disconnected, and every 3minutes its asked redial, our nearest telephone exchange is pithapuram- 533450 e.g.dt, andhrapradesh.
when i asked the bsnl employees they tell me un believable reasons.
kindly slove this problem.
yours faithfully...
land phone No :[protected]
address : 14-1-2
mainroad, pithapuram- 533450
East godavari Dist
Andhra pradesh.