BSNL — not able to connect to data modem

Address:

Maharashtra

I have a data modem of bsnl. it was working fine previously before 1year. but I havnt used it since last year. now I have recharge it. and when I am trying to connect it its showing error as a connection to the remote computer could not be established . you might need to change the network setting for this connection. do I need to do any setting? or the sim is expired?