Oracle Message ORA-24392 - no connection pool to associate server handle

ERRORno connection pool to associate server handle
CAUSEOCIServerAttach called in OCI_POOL mode but no connection pool found to associate the server handle.
ACTION1) Verify that OCIConnectionPoolCreate is called before calling OCIServerAttach. 2) Verify that the database link specified in OCIServerAttach matches with that of the connection pool database link.