I suspect user and password is wrong.
Since that mining pool require an account, you need using that user name that you signed with!.
Most mining pool allows us creating a worker starting with "1" and assigning a password.
If your user name is "user" then use:
-u user.1 -p x
If that mining pool allow assigning a password then use that password instead of "x"
Check if port is correct!
that's about it
The EXACT same command line (except for the path to the program) works for other miners, but not bfgminer.