Problem connecting to internet on Ubuntu 12.10

Question

I use the pon dsl-provider command to connect to internet through the terminal on Ubuntu 12.10. Lately, however the connection does not work and on plog, gives the following info:

aasthadua@ubuntu:~$ plog 
- Jan  4 19:00:46 ubuntu pppd[3404]: Connected to 00:25:83:1d:a8:71 via interface eth0 

- Jan  4 19:00:46 ubuntu pppd[3404]: Using interface ppp2 

- Jan  4 19:00:46 ubuntu pppd[3404]: Connect: ppp2 <--> eth0

- Jan  4 19:00:48 ubuntu pppd[3404]: Remote message: ^M^JYou are already logged in - access denied^M^J^J 

- Jan  4 19:00:48 ubuntu pppd[3404]: PAP authentication failed 

- Jan  4 19:00:48 ubuntu pppd[3404]: Connection terminated.

Also, if I supply the poff command, I get the following result:

/usr/bin/poff: More than one pppd running and no -a option and no arguments supplied. Nothing stopped.

I'm new to Ubuntu, and can't seem to figure this out on my own. Could anyone help me? (in as easy terms as possible)

Thanks.