Oracle UPDATE statement stuck problem

Execution of the UPDATE statement was found to be unsuccessful for half a day

Update Main_order Set order_source = ' 2 ', order_status = ' 2 '

Query which objects are locked

Select    object_name , Machine    ,    s.sid,    s.serial#from    v$locked_object l,    dba_objects O,    v$session S where      L. object_id = o.object_idand     l.session_id=s.sid;　

Three records were locked in the query.

Next: Use the following statement to kill the process (where 133,6071 is the sid,serial# of the above query)

Alter Kill ' 133,6071 '  alterkill'84,142'alterkill  '72,11243';

There's no problem when you execute update again.

Oracle UPDATE statement stuck problem