When I post https://www.example.com/ my meta tag information like meta title, meta image showing on all social media platform. But when I post www.example.com or mydomian.com my meta tag not showing.

here is my meta tag look like this:

 <meta property="og:title"content="my text"/>
 <meta property="og:type" content="website" />
 <meta property="og:url" content="https://www.example.com" />
 <meta property="og:site_name" content="example.com" />
 <metaproperty="og:description"content="my content."/>
 ... others meta