12c User connection ORA-01017 Bug

SYS@Sajid>connect <username>/<password>
ERROR:
ORA-01017: invalid username/password; logon denied
Warning: You are no longer connected to ORACLE.

@>exit

[oracle@Sajidserver01] /home/oracle: sqlplus  as sysdba

SQL*Plus: Release 12.1.0.2.0 Production on Thu Sep 3 11:42:00 2015

Copyright (c) 1982, 2014, Oracle.  All rights reserved.


Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, Real Application Clusters, Automatic Storage Management, OLAP,
Advanced Analytics and Real Application Testing options

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Proper Connect String
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SYS@Sajid>connect <username>/<password>@<dbname>;
Connected.
<user>@<dbaname>>show user;
USER is "username"