关于PLsql的问题

declare
  cursor c1(id number default 10) is
     select *  from "Contact" where "ContactID"<id for update;
begin
for h in c1(id=>20) loop
   if  instr(h."FirstName",'G')=1 then
     update "Contact"
     set "FirstName"=initcap("FirstName")+'G!!'
     where current of c1 ;
     dbms_output.put_line(h."ContactID"||h."FirstName");
   end if;
end loop;
commit;
end;
请问上面哪错了？提示无效数字