TwitterCard meta tags are supposed to use the attributes "name" and "content". OpenGraph tags use the attributes "property" and "content".
Twitter itself is smart enough to detect broken meta tags and discover the TwitterCard using "property" and "content", but other platforms that only implement parsing of TwitterCards and not OpenGraph may fail to correctly detect the tags as they're under the wrong attributes.
"Open Graph protocol also specifies the use of property and content attributes for markup while Twitter cards use name and content. Twitter’s parser will fall back to using property and content, so there is no need to modify existing Open Graph protocol markup if it already exists."