'We'd love feedback on your recent OnlyKey purchase' marked as spam


I received an email that was marked as spam. The headers show the following:

X-Spam-Flag: YES                                                                
X-Spam-Status: Yes, score=5.6 required=5.0 tests=DKIMWL_WL_MED,DKIM_SIGNED,     
        autolearn_force=no version=3.4.6                                        
        *  1.1 URIBL_GREY Contains an URL listed in the URIBL greylist          
        *      [URIs: sendgrid.net]                                             
        * -0.0 SPF_PASS SPF: sender matches SPF record                          
        *  0.2 HEADER_FROM_DIFFERENT_DOMAINS From and EnvelopeFrom 2nd level    
        *      mail domains are different                                       
        *  0.7 MPART_ALT_DIFF BODY: HTML and text parts are different           
        *  0.0 HTML_MESSAGE BODY: HTML included in message                      
        *  0.1 MIME_HTML_MOSTLY BODY: Multipart message mostly text/html MIME   
        *  0.0 HTML_FONT_LOW_CONTRAST BODY: HTML font color similar or          
        *      identical to background                                          
        * -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from      
        *      envelope-from domain                                             
        * -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature   
        *  0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily  
        *       valid                                                           
        *  0.0 T_KAM_HTML_FONT_INVALID Test for Invalidly Named or Formatted    
        *      Colors in HTML                                                   
        *  0.0 UNPARSEABLE_RELAY Informational: message has unparseable relay   
        *      lines                                                            
        *  2.5 SHOPIFY_IMG_NOT_RCVD_SFY Shopify hosted image but message not    
        *      from Shopify                                                     
        * -0.0 DKIMWL_WL_MED DKIMwl.org - Medium trust sender                   
        *  1.1 SENDGRID_REDIR Redirect URI via Sendgrid                         
X-Spam-Level: *****

I would not expect onlykey to send email that would be regarded as spam.

Any email can be flagged as spam