已经建好的job，怎么让它手工运行

已经建好的job，如何让它手工运行？
job号 22

linux下面登录数据库，

SQL>begin
  dbms_job(22);
  end;
  /


ERROR at line 1:
ORA-23421: job number 21 is not a job in the job queue
ORA-06512: at "SYS.DBMS_SYS_ERROR", line 86
ORA-06512: at "SYS.DBMS_IJOB", line 529
ORA-06512: at "SYS.DBMS_JOB", line 258
ORA-06512: at line 2


------解决方案--------------------
似乎没啥满意答案