How to import complex XML Types in Oracle SQL using XMLTABLE

I have the following XML Files completely imported in the table called ARCHIVDATA into one single cell called CLOB_CONTENT:

<AuditLog>
  <AuditLogEntry>
     <Header>1
     </Header>
     <Content>2
     </Content>
  </AuditLogEntry>
  <AuditLogEntry>
     <Header>3
     </Header>
  </AuditLogEntry>
  <AuditLogEntry>
     <Header>4
     </Header>
     <Content>5
     </Content>
     <Content>6
     </Content>
  </AuditLogEntry>
</AuditLog>

What I want as a result is the following table (table with two rows):

Header | Content
1 | 2

3 | NULL

4 | 5

4 | 6



How can I do that?

I already tried the following:

SELECT x3.header, x4.content
FROM (select xmltype(xml.CLOB_CONTENT) xmldata from ARCHIVDATA) x1,
     xmltable('/AuditLog/AuditLogEntry'
         passing x1.xmldata
         columns
             header XmlType path 'header',
             content XmlType path 'content'
         )x2,
         xmltable('/header'
         passing x2.header
         columns
             header varchar2(4000) path '.'
         )x3,
         xmltable('/content'
         passing x2.content
         columns
             content varchar2(4000) path '.'
         )x4
;/

What do I have to change to get the desired result table?