Google mail server is giving me 2 records via as an e-mail, both records are the same except one DKIM pass and other fail

Question

I receive the Googla mail test result as an XML file. It looks like this:

<record>
<row>
<source_ip>195.38.126.122</source_ip>
<count>3</count>
<policy_evaluated>
<disposition>none</disposition>
<dkim>pass</dkim>
<spf>pass</spf>
</policy_evaluated>
</row>
<identifiers>
<header_from>patrikx3.com</header_from>
</identifiers>
<auth_results>
<dkim>
<domain>patrikx3.com</domain>
<result>pass</result>
<selector>mail</selector>
</dkim>
<spf>
<domain>patrikx3.com</domain>
<result>pass</result>
</spf>
</auth_results>
</record>

and the other:

<record>
<row>
<source_ip>195.38.126.122</source_ip>
<count>6</count>
<policy_evaluated>
<disposition>none</disposition>
<dkim>fail</dkim>
<spf>pass</spf>
</policy_evaluated>
</row>
<identifiers>
<header_from>patrikx3.com</header_from>
</identifiers>
<auth_results>
<spf>
<domain>patrikx3.com</domain>
<result>pass</result>
</spf>
</auth_results>
</record>

how is it possible, that the same domains one DKIM pass and the second is fail? As there a debug, that I could search for? I do not know where to start.