remove a database service

Hi All,

i got one data guard:

   PRIMARY:                                                    standby

database name: EWFM01UAT                          EWFM01UAT

service name: EWFM01UAT                            EWFM01UAD

db_unique_name: EWFM01UAT                        EWFM01UAD

Then I did a switch over, and change service_name for both databases.

   standby                                                     primary

database name: EWFM01UAT                          EWFM01UAT

service name: EWFM01UAD                            EWFM01UAT

db_unique_name: EWFM01UAT                        EWFM01UAD

But after switch over, on primary side, I can't remove service_name EWFM01UAD:

SQL> exec dbms_service.stop_service ('EWFM01UAD');

PL/SQL procedure successfully completed.

SQL> exec dbms_service.delete_service ('EWFM01UAD');
BEGIN dbms_service.delete_service ('EWFM01UAD'); END;