I notice that you haven't used a TNS connect-string. Can you retry with the TNS connect-string .. and try from the same ORACLE_HOME that rman is running from.
I suspect that either
a) the password has changed (and your xxxxx is the new password) but RMAN and OEM are still attempting the old password
b) the TNS connect-string has changed and is pointing to a database different from that holding the RMAN catalog
I already googled this out and my issue is not with target, but with catalog. I appreciate your support.
Thanks for the support. My issue has been really funny as i was able to change the password of rman and the target is recognizing the new password. So i reset my rman password to existing password. Now my target is recognizing the password and all other databases are also connecting to catalog as the password is not changed.