ORA-00038: Cannot create session: server group belongs to another user

admin

ORA-00038: Cannot create session: server group belongs to another user
Cause: An attempt was made to create a non-migratable session in a server group that is owned by a different user.
Action: A server group is owned by the first user who logs into a server in the server group in non-migratable mode. All subsequent non-migratable mode logins must be made by the user who owns the server group. To have a different user login in non-migratable mode, the ownership of the server group will have to be changed. This can be done by logging off all current sessions and detaching from
all existing servers in the server group and then having the new user login to become the new owner.