Message Oracle TNS-12504 - TNS: listener was not given the SERVICE_NAME in CONNECT_DATA

ERRORTNS: listener was not given the SERVICE_NAME in CONNECT_DATA
CAUSEThe listener was not configured with a default service and SERVICE_NAME was missing from the CONNECT_DATA received by the listener.
ACTIONPossible solutions are: - Configure DEFAULT_SERVICE parameter in LISTENER.ORA with a valid service name. Reload the listener parameter file using reload []. This should be done by the LISTENER administrator. - If using a service name, Check that the connect descriptor corresponding to the service name in TNSNAMES.ORA has a SERVICE_NAME or SID component in the CONNECT_DATA.