EBS 12.2.4 integrated with OAM 11g authn/authz issues when already authenticated

Hi Everyone,

I'm having on SSO. I have a 12.1.3 EBS using OSSO agent and 12.2.4 EBS using Webgate agent. Both are registered on same OAM/OID

When I login into one environment successfully then tried to access the second environment, I am getting this error:

[2015-07-27T07:19:38.138-04:00] [oam_server1] [ERROR] [OAM-02054] [oracle.oam.controller] [tid: [ACTIVE].ExecuteThread: '2' f
or queue: 'weblogic.kernel.Default (self-tuning)'] [userId: <anonymous>] [ecid: f91825586436bd78:6508ab5:14eca667468:-8000-00
0000000000b3f5,0] [APP: oam_server#11.1.2.0.0] SSO session creation failed.[[
oracle.security.am.common.utilities.exception.AmRuntimeException: LoggedIn user is different than the existing session user
        at oracle.security.am.engines.sso.adapter.MultipleUserSessionAdapterImpl.shouldUpdateOnSubjectValidationFailure(Multi
pleUserSessionAdapterImpl.java:252)
        at oracle.security.am.engines.sso.adapter.AbstractSessionAdapterImpl.createUpdateSession(AbstractSessionAdapterImpl.j
ava:616)
        at oracle.security.am.engines.enginecontroller.SSOEngineController.createSession(SSOEngineController.java:3396)
        at oracle.security.am.engines.enginecontroller.SSOEngineController.processEvent(SSOEngineController.java:535)
        at oracle.security.am.controller.MasterController.processEvent(MasterController.java:596