plsql - When i create a trigger it gives an error saying it is invalid and failed re-validation -

i tried updating client_master table gave error idk why.i did update client_master set name='abc' name='xyz';

  create or replace trigger client_audit before update or delete on client_master each row begin     case          when updating             insert audit_client values(:old.c_no,:old.name,:old.address,:old.bal_due,'upd','1',sysdate);         when deleting             insert audit_client values(:old.c_no,:old.name,:old.address,:old.bal_due,'delet','2',sysdate);     end case; end; / 

try solution. hope helps.

create or replace trigger client_audit before   update or   delete on client_master each row    declare   begin    if updating   insert   audit_client values     (       :old.c_no,       :old.name,       :old.address,       :old.bal_due,       'upd',       '1',       sysdate     ); elsif deleting   insert   audit_client values     (       :old.c_no,       :old.name,       :old.address,       :old.bal_due,       'delet',       '2',       sysdate     ); end if; end; /